New Electric Skateboard

Happy pi day, everyone!

My skateboard was broken for the past five or six months, and rather than get it repaired, I traded it in for a new, more powerful model. For a cost of about $120, I now have a board that can go zero to 20 mph in four seconds. This is a pretty alarming speed and has finally gotten me to buy a helmet, but it also means I’m one step closer to becoming a Kourier. I just need to talk to Neal Stephenson about some engineering issues with those radial-spoke wheels …

For anyone interested in buying a board, I recommend going to eBay and looking for a cheap used one to try the idea out. My first board, a vaguely toy-like e-skateboard ($31 on eBay in 2004) had an 80-watt motor (still surprisingly powerful — it managed to tow four people at one point). I bought a few other cheap used ones, and then, having decided these things were indeed awesome, I decided to spend some more money on a proper board for getting around the city. I got a 250-watt Exkate Raptor 3.0 for $320, which I talked about in an earlier post.

This new board, a Pro Module 600, is also made by Exkate (now Altered Electric Skateboards):

The old 250-watt board was still not quite powerful enough to climb Somerville hills without complaint (I’m at the upper end of the 170-lb weight limit), but this new one has a 600-watt motor, which handles them no problem.

According to Science, 600 watts is about 80% of a horsepower.

This suggests that if you found a smallish horse (say, 75% the strength of a standard one), and started a tug-of-war using this new board, you could actually win.

This is of course dependent on friction and when the board can actually supply maximum power and so on. But let’s pretend it would work.






Edit: Taylor of Exkate posted with some technical info, and I answered some other questions in the comments. He mentions that if you want to order a board, call him (949.951.9500) and mention xkcd for free shipping (which can be significant). Disclaimer: They aren’t paying/giving me anything, they didn’t ask me to write this, etc. If you’re interested but don’t want to spend a lot yet, I recommend trawling eBay for a cheap board to try the idea out.

 

242 Responses to “New Electric Skateboard”

  1. invisibleandpink Says:

    A gadget for throwing squirrels up isn’t nearly as cool as an electric skateboard.

    Who is that person?

  2. Charlie Says:

    For those interested in electric transportation (especially of the do-it-yourself variety), pay a visit to the Endless-sphere forums - there seem to be a lot of really knowledgeable people on there talking about new battery and motor technology.

    I really like the idea of having an electric-powered bike. I think that would be a really cheap, efficient way to get around town fast and could replace a car or motorcycle in many cases. Imagine being able to do 35-40mph on the road with cars, and then turn onto a bike path (dial it down to 25 or so) and keep on going. You’d get a workout too, as you’d be contributing a fraction of the power yourself by pedaling. (And if it dies or runs out of juice, hey, now it’s a bike)

  3. xkcd Says:

    Charlie: I know a guy around here who got an electric bike when his license was revoked. The big problem is batteries — he used NiMH cells and the whole thing ended up costing about $12,000. The folks at Exkate tell me that I might be able to equip this one with lithium-ion batteries for $600, giving it a 60-mile range. That might be my project later this year when these lead-acid cells start to get old.

    Thanks for the link — when I start messing with the alternate cells, I’ll check it out.

    Invisibleandpink: It’s a thing from this post :)

  4. Chris Says:

    Having recently read Snow Crash, I can safely say that radial-spoke wheels are quite possibly “The only way to fly.”

    But, you know, on land.

  5. Joshua Says:

    It would rip off your arms probably though. Or you just might let go of the rope.

  6. y8s Says:

    oh hi I posted this on the LJ feed which is lame:

    I’d suggest the Assateague Island miniature horses. Do not call them ponies!

    http://www.nps.gov/archive/asis/horses.htm

  7. Josiah B Says:

    I, for one, am trying to figure out how you don’t veer away from the weight of the horse when you slacken the line.

  8. xkcd Says:

    Chris: When I was doing robotics, we spent an afternoon trying to come up with a way to make them practical. They seem to have a lot of inherent engineering problems, including that it’s not entirely clear how something can roll with them while keeping several of them in the same spot on the ground, even if you solve the making-them-telescope-efficiently problem.

  9. brad Says:

    Instead of battery-powered, how about putting a flywheel on a (recumbent) bike? If you could somehow get the brakes to regen the flywheel, you could use the flywheel as: 1) stored energy that lets you easily start back up from a stop, and 2) a gyro that keeps the bike from tipping over when stopped. Now that’s Science.

  10. Kree Says:

    Two diagrammatic figures find love in a hypothetical world. Cute :P

  11. Dave L Says:

    But what would happen if you were on a conveyor belt?

  12. Andy Says:

    I want one.

    Questions: What do you do when you reach your destination? Do you have a bike lock for it or somthing?

  13. Godman Says:

    I wrote a phisics paper on lifting squirrels with lasers. I got a 95% on it.

  14. Dave L Says:

    Ok, ok, to make up for my previous comment, you might find this post at Treehugger interesting - it’s about how Tesla Motors handles spent batteries:

    http://www.treehugger.com/files/2008/03/tesla-electric-car-batteries-non-toxic-recycled.php

  15. xkcd Says:

    Andy: Yeah, actually! I got a lock that fits around the front truck. With a hex wrench you could still take it off — I’ll either just not worry about that, or drill a hole somewhere near the nose to thread the lock through.

  16. peets Says:

    I once rode a bicycle equipped with a chainsaw motor. How noisy is your skateboard?

  17. Andrew Says:

    My brother made a really ugly bike with a weedeater motor a few years back. Two ruined bikes and a useless weedeater later, he realized he had made a gas powered break…

  18. atheist Says:

    Am I missing something? 600 watt 36 volt motor draws (nominal max) 16.6 amps, shouldn’t a 28.5AH battery last well over an hour, even after inefficiencies? The range should be well over 20 miles, not the 8-12 they are quoting. That’s only 25-37 percent efficiency :/

    And that’s assuming maximum amp draw the entire trip, with no regenerative braking (the board doesn’t have that, right?). Got a 30 mile long hill?

    Anyway, the reason I came to post was that my hobby right now is RC trucks. I have both nitro-powered and electric, and I’m intrigued with the idea of building an electric skateboard. Electric motors for these trucks can easily get past 500 watt, and if you’re willing to spend, 1200-2400 watts isn’t that hard to come by. That, and even the small nitro motors are usually ~1hp. Better ones can be in the 3-5hp range.

  19. Juho Mäkinen Says:

    Aawww. That comic is so cute, made me laugh =)

    - Garo

  20. ThemePark Says:

    So I guess you CAN lead a horse to water and make it drink too.

  21. xkcd Says:

    > Am I missing something? 600 watt 36 volt motor draws (nominal max) 16.6 amps, shouldn’t a 28.5AH battery last well over an hour, even after inefficiencies? The range should be well over 20 miles, not the 8-12 they are quoting. That’s only 25-37 percent efficiency :/

    Yeah! That’s been bugging me too, but I definitely have the board die pretty hard in well under an our of continuous riding. I followed a bike path about 3.5 miles and back (7 miles total), and for the last half-mile it had slowed down to walking pace. That was stop-and-go for a few of the miles, so not all at top efficiency, but the whole trip was still like an hour.

    I’m going to ask the folks at Exkate when I talk to them next.

    edit: I just asked them, and they said the 28.5 AH is a misprint, it’s actually 9.5, which makes it all add up.

  22. ryanknapper Says:

    I *knew* that guy levitating the squirrel was gay.

  23. invisibleandpink Says:

    xkcd, did you copy & paste the skateboarder from the fourth to the fifth panel in the comic at the bottom of the entry? He looks all blurred compared to everything else.

    You can also do REALLY COOL STUFF with the board, things like… http://www.turning-coffee-into-theorems.com/acceleratingphotons.jpg :)

  24. Jenni0206 Says:

    “I’d suggest the Assateague Island miniature horses. Do not call them ponies!”

    Actually, they are ponies. Miniature horses have a height standard: maximum of 34-38 inches (82-91 cm) at the wither (depends on registry) and have the physical phenotype of horses, where as ponies have different conformation entirely. Even your referenced website concedes that they average 12- 13 hands (48-52 inches) - have primarily evolved to a smaller size and pony-like hardiness due to the poor forage on the island (see: http://en.wikipedia.org/wiki/Island_rule). Even when “properly” fed by humans, they rarely achieve ‘horse’ height - or mini height. One should know by now that xkcd readers will actually fact check and disprove drivel.

    As an aside, miniature horses make awesome seeing-eyes for blind people.

    I would, however, die to see a Fjord vs skateboard incident. Can provide a variety of smaller horses for such experimentation, including the Fjord. They would love this game once they figured out what the hell was going on.

  25. Justin Marrese Says:

    Of course, mechanical power is basically force x speed. A tug-of-war doesn’t need much speed, just more force, so you can just win it with better gear ratios. I have a feeling the average quadruped can’t down-shift so easily.

    With a good enough gearing, and plenty of time, I think that squirrel in a running wheel would be able to win against the horse.

    Good thing too, considering the two people in the comic are busy doing other stuff now ….

    (And yes, electric motors produce more torque near stall speed - but they are producing almost no power. Torque and Force are not the same as Power…)

  26. Mike Purvis Says:

    For the adventurous, there’s always Trevor Blackwell’s Eunicycle.

  27. A Says:

    Re the ppl talking about electric bikes:

    They exist, and are fairly mainstream. There’s a few to be seen around Cambridge (the UK Cambridge not rhe US one, and one of the few UK towns where ppl use bikes of any sort), I think being rented out by some company. They’re not massively fast (like, 20mph top speed, I’d guess from watching them) but they’re also barely any more bulkey than normal bikes (just a kinda fat box around where the pedals’ sprocket). No idea on the range or battery life.

  28. Arvin Bautista Says:

    Hey, I was wondering what you do about getting up and down curbs… is it easy to pick up/put back down, if you got off of it would it just keep rolling until it ran out of juice? How good is it about rolling over cracks? I used a skateboard to get around in college but my apartment now is in a relatively hilly area (I only weigh 145), but moreso the curbs and cracks are more punishing. A bike is too big to lug around, and gas prices are so high.

  29. Adam Says:

    Wow. The power adapter looks a lot like an XLR cable. Or at least that’s what the 12 pixels that compromise that tiny image make it look like.

    Seems like a silly design decision.

  30. Liryon Says:

    Does this blog comic constitute another reference to making out with yourself, ala comics 105 and 267? I think it does.

  31. Runa Says:

    does it mean that I’ll fall in love with someone if I buy that board?

  32. Alex Says:

    I read your other blag post about electric skateboards, and I was wondering what made you decide exkate was a better company to do business with than eglide.

  33. Charon Says:

    Why not take a look at some the new transistor battery cells that are going on with cars, might be a little heavy but larger power supply and greater efficiency. Also you may want to open it up and check the motor efficiency by plugging it in the wall with an amp measuring tool and a small generator. You could also just strap some Jet assist rockets to it and fly :D

  34. Ben Says:

    How secure is the wireless controller? It seems like someone (not the rider) could have a lot of fun with a well-tuned transmitter.

  35. Cosmic JuJu Says:

    So, curiously, how is the traction on the wheels? If you want to tow a pony, i imagine you’re going to need to grip the road fairly well.
    Also, comes in handy when taking tight curves to dodge airborne squirrels.

  36. PapaG Says:

    http://www.popsci.com/diy/article/2008-02/motorized-skateboard-speed-happy-gearheads

    it may require alot more work, and cost more, but it looks way more bad-ass

  37. Alex Says:

    Please tell me you did’nt draw two dudes making out. Or is that supposed to be a guy making out with himself?

  38. Alex Ponebshek Says:

    Dudes making out is great!

    Anyway, the term “horsepower” is based on sustained output of a horse. I think you’d need about 10hp to actually win at tug-of-war against a normal horse.

  39. MythGuy Says:

    I liked the little comics in the posting, though, they both seem to be guys…

    Anyway, that’s pretty cool! The other day I ventured outside and ended up talking to some guy with an AWESOME gasoline powered scooter. I want both of them! :D

    You should try making people do double-takes by having a GPS Navigation unit though. That’d be fun.

  40. Nexox Says:

    I have spent quite a few hours of free (class) time designing a nice speedo for my skateboard that’d feature a large red LED readout, inspired by YT’s board. I even went so far as to spec out the GPS chip, microcontroller, and the algorithm to merge GPS and accelerometer data. I have no idea how useful it’d be to download my exact route between classes onto a campus map every day… but I sure as hell would do it. Unfortunately I’ll be leaving school soon and I doubt that I’ll ever have need for my plank again. I guess I’ll have to switch over to making replica full scale mideval siege weapons or something.

  41. G. M. Palmer Says:

    Jenni-O

    One should also know we disapprove of asshattery.

    GMP

    read.my.blog

  42. three08 Says:

    they’re stick figures. if it upsets you that much to think someone might draw two dude stick figures making out, imagine one or both of them is a chick with short hair. or, alternatively, get over yourselves and/or grow up.

    i haven’t done that much skateboarding but wouldn’t it be hard to maintain stability at 20 mph? and then you’d start wobbling and death or at least high-speed interactions with an uncomfortably large area of pavement would ensue?

  43. Alex Says:

    three08: Even the manliest xkcd chick has visible hair. Not that there’s anything wrong with 2 dudes making out, but come on man…

  44. Anonymous Says:

    Hmmm….I might just have to try one of these things out for myself…

  45. skilaatara Says:

    Alex: Can you prove that all the hairless stick figures in xkcd comics are male? That does seem to be the case in all the comics where gender is specified, but if some guys can have hair (http://xkcd.com/377/, http://xkcd.com/351/), why can’t some girls shave their heads? I henceforth claim this here diagram for the glorious cause of bald lesbian stick figure love!

  46. xkcd Says:

    I once rode a bicycle equipped with a chainsaw motor. How noisy is your skateboard?

    Pretty quiet — there’s a mildly noisy medium-pitch hum at low speeds, but it falls silent when you go up to full (and the motor gets noisier). Quiet enough that I can ride it on the street and it isn’t too loud.

    Hey, I was wondering what you do about getting up and down curbs… is it easy to pick up/put back down, if you got off of it would it just keep rolling until it ran out of juice? How good is it about rolling over cracks?

    It can jump down the curbs — to go up them I’m not smooth enough to kick the nose up that high so I just stop, grab the nose, lift it up, and get back on. But it’s all pretty fast. The wheels are large so it takes a pretty big crack to be a problem — has to be a couple inches wide and fairly deep. It goes up one-inch discontinuities okay. If you get off the board and/or let go of the controller, it stops pretty reliably.

    I read your other blag post about electric skateboards, and I was wondering what made you decide exkate was a better company to do business with than eglide.

    Well, Exkate has the wireless controller (they’re being asses about the patent, apparently, which is why E-Glide boards aren’t wireless. Exkate is a lot bigger and more widely bought from, and I got a general sense of better design from them. Also, E-Glide didn’t have a cheaper board in my price range.

    The Exkate folks also have a pretty negative opinion of E-Glide hardware, but of course they’re biased :)

    How secure is the wireless controller? It seems like someone (not the rider) could have a lot of fun with a well-tuned transmitter.

    Yeah, you could probably do that, although they sync to the nearest board when you turn them on so you can use two of them nearby. So they’re not totally open.

    Please tell me you did’nt draw two dudes making out.

    ::eyeroll::

    i haven’t done that much skateboarding but wouldn’t it be hard to maintain stability at 20 mph?

    The boards have special trucks that are good for high-speed stability. After about 10 seconds at that speed, you have a good feel for it — I never wobble.

    For perspective here, I’ve been riding these around for quite a while and have never been hurt falling off. I’ve stumbled once or twice and landed off the board on my feet. They’re really a lot safer than longboards, I think — most of the longboard accidents that I’ve read about happen because there’s no easy way to stop at high speed.

  47. Anonymous Says:

    Lithium-ion sounds an unlikely choice, they’re kind of bad at high-power output. I’m thinking those are likely lithium-polymer batteries (or if they are not, they should be).

    Lithium-polymer batteries are a lot more exciting, especially with the increased risk of awesome explosions!

  48. Natinia Says:

    If it really bothers you children so much, realize that both characters are from his own blags talking about things he will/wants to do. Therefore its merely timetravel-selflove, if you’re uncomfortable with *unconditional* love.

    Happy pi day! sadly I am pieless… thankfully cookies*r^2 also.

    I’m seriously considering getting an electric skateboard, but the problem is i’ve no where to go… maybe when i move in a year or two…

    Isn’t 20mph a little excessive, especially in 4 seconds? Sounds to me like much pain waiting eagerly on the brink of existence, but maybe because i spend so much time in the virtual world that i forgot how to balance properly.

    You should use a complex series of lazers to help you manipulate the (how heavy is it?) massive board into THPS skate moves. You get bonus points for using science.

  49. Taylor Says:

    Just for clarification - it’s a typo on the AH for the Exkates.

    it’s 36V and 9.5AH… someone added both the voltage and the AH and you only get to add the voltage up in a series.

    We’ll change that in the literature shortly.

    Also, it is an XLR connector for the battery charger. The reason for this is that they’re cheap, easily available and perform the desired function. Consider it a case of “If it ain’t broke, don’t fix it”

    If you have any more techie questions, feel free to shoot me an email.

    If you’re interested in purchasing a board, give me a call. Mention XKCD and I’ll throw in free shipping.

    Thanks,
    Taylor
    Exkate
    949.951.9500
    taylor@exkate.com

  50. Handsome Says:

    Now, if you were to put this skateboard on a treadmill and turn them both on, what would happen?

  51. xkcd Says:

    Now, if you were to put this skateboard on a treadmill and turn them both on, what would happen?

    Ryan North would appear out of nowhere.

  52. Jerry Kindall Says:

    Nice footomobile.

  53. Not today again… « The Unapologetic Mathematician Says:

    [...] today again… XKCD did it at the top of today’s post. The first reference to the day. I’m not going to get all ranty. I’ll just refer to my [...]

  54. myself Says:

    Am I the only one amused by the fact that the skateboard he bought is a Raptor?

  55. Atheist_Pending Says:

    No

  56. atomofconsumption Says:

    i’m not sure if i missed this somewhere.. but does it have brakes? is that a remote control in your hand?

  57. atomofconsumption Says:

    k, i found the answer (wireless controller).

  58. Ben Tobin Says:

    I’ve been actively researching electric bikes for this summer, since my stone-age non-electric bike was stolen.

    I’m considering this $500 unit: http://www.sbebc.com/pages/SantaRosa.html

    Or maybe a kit for converting a bike myself: http://www.werelectrified.com/index.php?cPath=2

  59. dckx Says:

    I noticed that too, myself.

    But with these skateboards, do you actually have to know how to skateboard? I’ve tried before, and that crap’s hard! Plus I have terrible balance when I’m standing on something other than my feet, so does it turn roughly at all? And how well do they work on normal grass?

  60. Cesium Says:

    “Am I the only one amused by the fact that the skateboard he bought is a Raptor?”
    I wonder how many HP a raptor is? Also, how much of a squirrel could 600 watts levitate?

  61. Ron Says:

    You can get electric motors for bicycles for fairly cheap, if you’re willing to pedal on the uphill parts. I believe a friend of mine priced a whole setup out for about $1200.

    I’ll ask him for a link.

    I know, biking is lame compared to cool skateboarders. I ski instead of snowboard too. Old school 4 life.

    And personally I salute your stick figure love story. Truly love transcends gender, or any visible genitalia.

  62. dckx Says:

    “Also, how much of a squirrel could 600 watts levitate?”

    From my math, it would take 2,016,667 of these skateboards to lift a squirrel. So with one skateboard you could lift 0.0000495% of a squirrel which is like, what, half a hair? Not a lot, regardless.

    In case I calculated wrong:
    It takes 1.21 GW to lift a squirrel.
    1.21 GW=1,210,000,000 W
    Divided by 600=2,016,666 with a remainder of 400 watts, which means it would take 2,016,667 to fully lift it.
    100 divided by 2,016,667= 0.0000495% of a squirrel could be lifted with one board. Somebody correct me if I did that wrong.

  63. Kapura Says:

    You need some of those reverse bumper stickers to stick to windows. Then you could teach the locals to signal their turns :D

  64. cleverdan Says:

    ugh.

    it’s such a blunt shock to find people who still haven’t converted to metric.

    but. the real reason why i am writing this; does exkate sell to australia?

  65. ILAN Says:

    If you are looking for a MUCH lighter and higher tech Electric Skateboard, check out the Metroboard (http://www.metro-board.com), Designed and Made in Portland, Oregon, USA! The Metoboard uses High Power Lightweight NIMH batteries, has a 450 Watt motor, and get a 12 mile range with a 22 lb skateboard, making it much more portable. Exkate’s products, such as the Raptor 4.0, can’t boast that kind of range, and they weigh 50 lbs, a real back breaker!

    Although you pay a bit more upfront, NIMH batteries last roughly double the number of recharge cycles compared to SLA, so in the end with Exkate, you’ll end up paying more when it’s time to to buy the second set of batteries, and you’ll be stuck with a much heavier product! Metroboards are currently being discounted by $50 for the month of March+ Free US Shipping! Prices start at $449. Check it out!

    Email info@metro-board.com with any questions.

    -Ilan
    Metroboard Designer and Builder
    Portland, Oregon

  66. Lilium Says:

    Interestingly enough, Einstien was born on Pi Day…

  67. Lilium Says:

    Interestingly enough, Einstein was born on Pi Day…

  68. Alexey Feldgendler Says:

    The outcome also depends on the motivation of the horse.

  69. Simon Says:

    170 pound limit huh? Guess that rules my 6′1″, 200 pounds out…damn…

  70. mr_monolith Says:

    I wonder if we could make electric surfboards>?

  71. chrisdonia Says:

    I totally squeed myself at this. Self-referential tongue-in-cheek nerdgasms rock!

  72. SimonB Says:

    The entire post is all the more amusing for imagining the horse’s inner monologue throughout.

  73. holden Says:

    andy (weedeater motor): my cousin and i found that chainsaw engines are good for powering BMX’s. you need to gear it down a bunch of times, its insanely noisy, the exhaust tends to burn your leg, and it takes about a block to speed up. but all things considered, it was probably the most fun thing i have ever ridden

  74. holden Says:

    oops. missed ‘peet’ post. glad to see someone else has enjoyed it.

  75. ILAN Says:

    Simon,

    The Metroboard doesn’t have a 170 lb weight limit. The recommended maximum rider weight is about 220 lbs.

    Ilan

  76. Ace_NoOne Says:

    Great - and I was just about to buy one of these

  77. Cesium Says:

    dckx: “It takes 1.21 GW to lift a squirrel.”
    Nope, 1.21 JW (jigawatts). Completely different. ;)

    mr_monolith: “I wonder if we could make electric surfboards>?”
    Well, the whole point of a surfboard is to use the wave for power. You could attach a motor for getting out to sea but it wouldn’t be much use until it approaches jet ski power.

  78. Charlie Says:

    @Randall/XKCD

    > Charlie: I know a guy around here who got an electric bike when his license was revoked. The big problem is batteries — he used NiMH cells and the whole thing ended up costing about $12,000. The folks at Exkate tell me that I might be able to equip this one with lithium-ion batteries for $600, giving it a 60-mile range. That might be my project later this year when these lead-acid cells start to get old.

    For that amount of money, your friend could have gotten this beauty! I want one of those…

  79. JTMILLER Says:

    To quote the wiki

    Horsepower from a horse
    R. D. Stevenson and R. J. Wasserzug published an article in Nature 364, 195-195 (15 July 1993) calculating the upper limit to an animal’s power output. The peak power over a few seconds has been measured to be as high as 14.9 hp. However, for longer periods an average horse produces less than one horsepower.

  80. Ace_NoOne Says:

    > To quote the wiki

    Please, don’t ever call Wikipedia “the wiki” - that’s just wrong…

  81. NatchDan Says:

    More Snow Crash comics please.

  82. Cesium Says:

    Knowledge is power. If you taught the horse physics, would it win?

  83. TheTeatowel Says:

    Aaahh Somerville hills…. terrifying to go down on rollerblades without decent brakes.

  84. Josiah Says:

    I thought you might enjoy this :
    http://pi.ytmnd.com/

  85. arbivark Says:

    friend of mine mentions http://www.pal-v.com/ (more flying car than skateboard.) i used to own a few shares of zapworld.com, which makes/sells electric bikes and a range of other electric vehicles. not saying better than the e-raptor, just has some additional product. horse vs horsepower point has already been made.

  86. Pax Says:

    Yes! String theorist burns are never out of style.

  87. Benjamin Says:

    Hmm.. your tom foolery with this skate board has me thinking up one of my own.

    Two wheels rather then four, with the center of gravity below the medium of the wheels.

    Interchangable battery packs (have a set at work charging and one at home.. this way, no down time.)

    And a smexy white finish..

    EVIL PLAN HATCHING!
    ~oh.. its a boy
    ~Tweet.

  88. Andrew Says:

    Powered skate board is pretty cool I guess…but check this http://www.ebikes.ca/projects/Emanual/ out. A powered skateboard with only two wheels opposite each other that (almost) automatically balances its self.

    (ie picture a skate board, now, take the front two wheels, then move the back two wheels into the centre, and attach a motor to each of the wheels, and add control electronics to actuate the motors in such a way as to keep the board level)

  89. Cesium Says:

    Seems like a Segway, only harder to stand on.

  90. Ron Says:

    I’ve been looking at getting a goped ESR750EX electric stand up scooter (http://www.goped.com). There’s a possibility they may be ramping up to Li-Ion batteries in the future although right now they use SLA.

  91. Felis Says:

    So, to repeat myself: when’s your illustrated physics textbook going to come out again? =)

  92. heather (errantdreams) Says:

    The idea of using one of these on the hills of Somerville anywhere near the wintertime is frightening at best. Simply walking down the ice-covered hills and remaining upright was always a challenge, although I did live up a particularly steep hill at the time. Good to have that helmet!

  93. Ron Says:

    Electric Motor for bikes

    You have to put it on yourself, but it’s a lot cheaper than 12 grand.

  94. Binks Says:

    Is that a typo in the post? You said that you got this new board for $120. Looks like it sells for $470 to me.

  95. Frankie Robertson Says:

    @Binks: Traded in, that means: old board + $120 = new board.

  96. NO_U Says:

    http://en.wikipedia.org/wiki/Horsepower#Horsepower_from_a_horse

  97. Felstaff of the Forums Says:

    “The electric skateboard, but of course
    Has enough torque to drag a small horse
    But that kind of kinetic
    Don’t compare to magnetic
    Elevation of squirrels by force.”

    And now you can see why, of at least 11 submitted, not one of my limerickeries have made it to limerickdb :(

  98. Domenic Says:

    Hi there,

    I actually am lagging just a bit behind you in my electric skateboard love affair. I bought one of those eBay boards, got it stolen, and then bought another, which is currently in limbo—need to get a MechE over here, as my math-major brain doesn’t really know how to diagnose all these wires on the inside. But as someone who’s been there, could you help me out with some buying questions for future stages of this relationship?

    1) Noise!? These things are very loud going over anything with discontinuities, such as sidewalks, brick paths, or cobblestones. Some earlier blag post mentioned getting an electric skateboard with rubber wheels, but I haven’t found very many of those. I would also imagine this would have some bearing on shock absorption…

    2) Wireless control? I really like the current foot button + foot brake system on the eBay board, but clearly this is not a popular system. How does the wireless remote control compare to this system, in your opinion?

    3) Price? The Pro Module 600 you mention is definitely not $120… I guess that was the price difference for the upgrade? Generally, is it really worth it?

    4) Size and weight? I like the shortboard form factor of the eBay board, but this is again pretty unpopular. Similarly, the eBay board is like 27 lbs, whereas the Pro Module (for example) is around 40. How much do these differences affect you?

    Think that’s it… hope you can help :). Feel free to email me (domenic@domenicdenicola.com) as well. The internet is not as helpful on these kinds of things as I’d like it to be.

  99. Josh Says:

    Keep in mind that the term “horsepower” has been reduced over the years to make stuff sound more powerful than it actually is (My physics teacher told me this). So 80% horsepower is probably closer to 80% humanpower (again, according to my teacher). So the skateboards probly a bit stronger than you =)

  100. Zoë Says:

    What I think I really love about xkcd is the bonus humor from the blag and then the bonus bonus humor from witty commentary from readers of the blag. *bathes in the glow of good wit*

  101. Zoë Says:

    Also, you know, the fact that every time someone mentions a specific xkcd comic, I say “Oh, god, that one is one of my favorites!” I realized I was doing that and probably ought to stop, as when ALL the comics are your favorites, it somewhat defeats the purpose of a ranking system… :(

  102. DoubleAW Says:

    Yeah, I think it does, since he was doing both of the experiments. Making out with yourself sounds unusually fun. And weird.

  103. Zak McKracken Says:

    It seems noone else pointed this out yet, so I have to:
    One HP is the power an average horse can sustain for a whole day (like, when pulling a cart or turning a mill) and is about 735 watts. For a short time, it can do 20 times that without problems (says wikipedia).
    Also, As others have pointed out, in a tug-of-war, only static force counts, not power. And since the batteries will only supply a certain maximal current, you will probably lose agains any horse, pony or miniature. Even if we forget about mass and firction and stuff.

    But if you raced a horse uphill, you’d beat it if the distance is too long (or the hill too steep) for proper gallopping. Reason: The horse is much heavier than you plus the board, so you’d get more speed for the same power output.

    This would of course end entirely different if squirrel-Girl and E-board-Boy teamed up, because there’s a lot of things you can do with 2MW electric power, a laser and an electric skateboard …

  104. Alexandre Gauthier Says:

    Dammit. Now I need to read Snow Crash. Again.

    Twice if possible. And wish this book could never end.

    I want to be a Kourier, too.

  105. Alice Yu Says:

    Hmmm… actually, I seriously doubt that you could beat a small-ish horse in a tug-of-war. For one thing, “horse”-power is actually based on the power supplied by a pony, harking back to the days when they were trying to sell the notion of using engines rather than horses to pull railway cars. If you compare your engine to the number of ponies it can equal (ponies being weaker than horses), it sounds more impressive. So really, 80% horsepower would more accurately be described as 80% “ponypower.” And since strength doesn’t scale linearly, you’d have to be competing against a REALLY small-ish pony to get 75% strength. Maybe a Shetland yearling. Which would be kind of cute, I suppose.

    Also, horsepower (ponypower) is an average value of the force that a horse (pony) could supply over an extended time. The time involved in hauling railway cars all day, for instance. But in a tug-of-war, which involves relatively short bursts of energy, that pony would yoink you right off your skateboard and drag you around a bit while his pony friends point and laugh.

    Not to mention that your OWN strength would be the limiting factor in the first place, unless you tied the rope to your skateboard.

    However, all of these considerations are rendered null and void due to the sheer awesomeness of that illustration.

  106. Alice Yu Says:

    Ah, oops… I see others have already pointed out what I wrote in my comment. I should look through the comments before posting…

  107. Cesium Says:

    “This would of course end entirely different if squirrel-Girl and E-board-Boy teamed up, because there’s a lot of things you can do with 2MW electric power, a laser and an electric skateboard …”
    Hmm… what about a Dyson laser and a gravitational wave surfboard…?

  108. Jonathon Ronchetti Says:

    fuck you, mythbusters are awesome.

  109. Ted H Says:

    Mad Props on the Snow Crash Reference, dude! YT was amazing, and the first chapter was the best of anything I’ve ever read (mostly because I am a ‘za mercenary myself).

    I might, just might get one of those skateboards. Grand Forks, ND (my stomping grounds) is prime area for one of those - all the flat you could want, truly amazing.

    TRH

  110. Acid Says:

    A gadget for drawing horses would be good

  111. Acid Says:

    The visually impared Captcha is pretty good

  112. JP Says:

    You make me want to get a board to go from the train station to work. It would have to be light weight enough to carry on the train.

    and

    every time I see that comic I have to giggle.

  113. eitje Says:

    interesting thought, Cesium. Maybe that’s how the Silver Surfer flies through space.

  114. Jodyo Says:

    regarding today’s comic….

    EEWWWWWWWWWW!

  115. Dane Says:

    sorry dude, i love your comic and your blag and all, but an electric skateboard is one of the stupidest, laziest things i have ever heard of. you need to learn the joys of cycling.

  116. SolidHydrogen Says:

    To the guy who asked if they sell to Australia, I live in Denmark and have a Slash Bat 250 from exkate, and when talking on the phone with them, it sounded as though they weren’t unfamiliar with international orders.

    Some complaints you should watch out for: It is WAY heavier and bulkier than I was expecting when I read the specs. You read 27.5 pounds and think, “that’s not so bad… I can pick that up over short ranges.” Living in Europe, I got it with the idea of going board-train-board or board-bus-board, but its a pain. I do like the idea of locking it up like a bike instead of taking it around with me, so I’ll have to give that some more thought. Also, top speed is freakin scary. Xkcd claims he can ride it stable, but although I’m pretty athletic, I start to get wobbly at about 70%. That’s alright with me, because there’s normally no need to go that fast (I like cruising around on the board as opposed to getting someplace quickly). Finally, I would not at all recommend this for folks who aren’t used to riding boards of some type or pursuing other athletic endeavors. Watching my dad and gilfriend try to awkwardly keep their balance made me pretty nervous.

    xkcd: Have you had any problems with drive wheel wear? Mine is still pretty new, but the clearance between the wheel and drive casing seems awfully small. I feel like I’ll be grinding it up in no time and was wondering if you’ve found this to be the case.

    Despite the fact that it wasn’t exactly what I was anticipating, I have to say it is sheer awesomeness. I’ve made a lot of unexpected new friends, from little screaming arab children to chemical engineering professors. I’m at that point in life where I need something to keep me young, and this is the most fun I’ve had in a long time.

  117. Adam Says:

    How do these hold up in the rain? I’m thinking about something like this for commuting (currently ride a motorcycle for that) but it’s only about 4 miles each way…

  118. StaticSignal Says:

    I’m looking into getting some sort of electric board, but I’ve got a bit of a strange question.
    I’m only 97.2lbs (I’m 20 years old- weird, eh?), and I’m worried. Would the Exkate boards be TOO fast for me? Would I be able to keep them stable with my meager mass?
    Should I stick to a toy-like board instead? I really don’t want a wired controller. =(

  119. michael Says:

    StaticSignal:

    no, get the exkate board. I weigh about 100 pounds and will get one which supports riders up to 260 pounds because that would allow me to have a passenger with me. (that and for the speed.)

  120. Mike Says:

    WOw… a ball pit and a skateboard? I wish I were you… Actually, I don’t. Cause then I’d have to be funny all the time, and that would be too much work.

  121. Skates/board « Angel Says:

    [...] pretty actively in the market for a skateboard and/or skates right now.  So of course it gets blogged about and now it’s probably a seller’s market for the things on Ebay.  Hopefully everyone is [...]

  122. William Says:

    To Brad, who posted “Instead of battery-powered, how about putting a flywheel on a (recumbent) bike? If you could somehow get the brakes to regen the flywheel, you could use the flywheel as: 1) stored energy that lets you easily start back up from a stop, and 2) a gyro that keeps the bike from tipping over when stopped. Now that’s Science.”

    Flywheels don’t have to be that heavy, of course, they just have to spin fast, so it wouldn’t have to add more than 2-3 pounds to the bike.
    However, the gyro-effect would start as soon as you started braking, so during the 10-50 meters until the read light, you wouldn’t be able to turn your bike. Or, well, you could, but depending on what axis you mount the flywheel on, you’d get a hell of a precession.
    It’d be great for shows (riding sideways on one wheel, in outwards circles), but for practical applications, I think I’d choose the bike that doesn’t launch me sideways into traffic ^-^

  123. Cooley Says:

    This is actually how I plan to get around college campuses, as soon as I can get some money to buy one.

    It’s either that, or get one of those Razor scooters that fold so I can stow it during class.

  124. amy Says:

    why don’t we do more of this in physics? theres so much scope for love through science

  125. RF Says:

    Without radial-spoke wheels, CHISELED SPAM is what you will see in the mirror.

  126. Zinder Says:

    XKCD said,

    but it also means I’m one step closer to becoming a Kourier. I just need to talk to Neal Stephenson about some engineering issues with those radial-spoke wheels …

    I can’t believe nobody asked this.. maybe you’ve explained it in another post that I can’t find?

    What are you doing for a magnapoon? I mean, I suppose you could just do something retractable with a big-ass electromagnet on the end… but, I’d like to see what you came up with — especially for one-handedly operating the retraction and magnet on/off… plus, is there anything other than skill keeping you from putting a windshield out?

    Also. out of idle curiosity. Is it legal to ‘poon someone like that? Minor consideration, I know… but I wonder…

  127. Cesium Says:

    Well, you could just position it low enough that it couldn’t hit glass. It could all be controlled with the remote, and maybe mounted on the front of the board. Just make sure you don’t hit a lamp post or something.

  128. Clumpy Says:

    The little romantic cartoon at the end is pretty much the reason why nothing can compete with xkcd.

  129. AC Propulsion Guy Says:

    I’m probably way slow with this, but you misspelled “Traveling Salesman” — only one L in traveling.

  130. It's travelling Says:

    AC Propulsion Guy: No he didn’t. Travelling is acceptable, even though firefox catches it as a misspelled word. Do a web search.

  131. b-dog Says:

    I didn’t actually take the time to read every single post on here so I’m not sure if someone mentioned this. I’m in China right now and it is the first place I’ve seen electric bikes. They are quite prominent in good weather. They seem to be practical, and affordable, only a few thousand yuan (about 7yuan to one US dollar).
    It seems that in my city everyone who is over 23 and doesn’t have a car has an electric bike. And my city has 8 million people in it.

  132. Paul Says:

    “Is it legal to ‘poon someone like that?”

    I’m sure he has some other meaning than the one I’m thinking of, but seriously?

  133. Jeremy Says:

    Instead trying to find a small horse of >80% of a horsepower you could just go with a fully grown horse missing one leg.

  134. Jeremy Says:

    oops meant ‘<’

  135. BC Says:

    Re: today’s comic, “Important Life Lesson”

    I think a children’s choir singing “Jesus Loves Me” as soon as Jay-Z’s album “American Gangster” ended ranks up there alongside the Power Ranger theme.

  136. ThemePark Says:

    Regarding today’s comic. Pft. The Powers Rangers theme is a thousand times sexier than all of Barry White’s songs put through an all-night shuffle all marathon.

  137. Cloud Says:

    When she didn’t leave the room after music from Final Fantasy VII started playing, I was optimistic. When she told me she cried when Aeris died, I knew it was something special.

    (When she told me moogles got her hot, I felt it all slip away …)

  138. Nut Says:

    I can’t resist…
    “Sit on my face and tell me that you love me!”

  139. Cesium Says:

    And when it started playing my songs in Fibonacci order…

  140. Kobra Says:

    That’s freaking awesome. I want one, but I’ll probably need two (one for each of my very fat legs).

  141. volock Says:

    I just wanted to say if you ever wanted to go man-o-e-man-o with a minature horse I have a couple if you ever find yourself in Albuquerque, NM.

  142. Nico Says:

    Hi.

    About Important Life Lesson

    I once did that and I ended up on the music on Miyazaki movies which it turns out was not bad at all to set the mood; It’s kind of classical.

    I selected very carefully as well and it was some pink floyd because it’s my favorite band… I like Pink floyd so much I couldn’t concentrate on the sex…

    So, a good choice is not necessarily something you really like!!!

    Go Go Power ranges doesn’t fit in any of these categories and it’s just hilarious.

    Nico

  143. The Scarp Says:

    This electric skateboard industry might completely take-over, in which case kids would no longer get “Kick, Push.”

  144. JavaSucksMan Says:

    > What are you doing for a magnapoon?

    I’ve been riding the exkate for years (I have 3 in various states of repair)..
    Last summer I grabbed hold of my roommates pickup.
    I’ve bumper hitched many times with an ordinary board, but this was the first
    (and last) with a powerboard. After exceeding the top speed of about 22 mph,
    I decided to hang on and hitch my fate to the truck…..
    At about 35mph the board kicked out….
    (BTW, 50 pound boards kick out a lot harder than regular skateboards).
    Shouldn’t have been wearing flip-flops, but it was a spur of the moment thing.
    Came down perfectly on the flip-flops, and did a Fred Flintstone bumper hitch until I came to a stop… tore up the battery pack, but,
    hey, nothing lasts forever.

    The exkate X-24 rocks…. accept no substitutes.
    (got to try a Li Ion battery pack up at the factory,
    about 3 mph faster, 15 lbs lighter, double the range,
    but they have not yet decided to market them…
    charging hazard

  145. Drithaan Says:

    XD

    “Cool! I just gave a Helicopter Cancer!”

    This is why I read this comic.

    Also; did today’s comic make anyone else think of “Poisoning Pigeons in the Park”?

  146. joecentric Says:

    I gotta say, I truly appreciate the attention to detail here. Notice that the horse is sliding, but the skateboard’s wheels are locked (at least, that’s how I read it). With a little technical license, this might wave away the obvious differences in weight, given the standard variation between the coefficients of static and kinetic friction.

    Bravo, xkcd.

    Okay, now I’ll have my coffee, and get a little less smart/more smart (depending on whether what I said makes any sense).

    Cheers,
    –joe.

  147. Cirujano Says:

    This is a fun thread… I have an Exkate 3.0 I bought on Ebay for $250 (cosmetic blemish).

    I ride it almost everyday and have the same experience of getting stopped constantly to answer questions. I have ridden skateboards and snowboards for over 20 years so this is kind of a natural form of transport for me. I agree with the poster above, though that watching newbies try to ride this thing is terrifying.

    I chose the 3.0 because of the weight. I pick it up and carry it when I go into starbux or whatever. The 4.0 was just too heavy. I weigh 170 lbs and the thing goes just fast enough for me. I don’t need to go any faster than that.

    I did hit a curb and had to replace a cracked baseplate and bent kingpin. I also replaced the bushings to a stiffer (blue colored) model which I HIGHLY recommend if you weigh > 150 lbs. They messed up and delayed my order but it got here eventually.

    All in all I am VERY happy with my purchase in that it has paid for itself in gas/parking costs and is A LOT of fun.

    I am investigating converting to 24V 10Ah LiFePO4 batteries (which would cost around $600) to lighten it up and extend the range but I can’t find any record of anyone having done so before. I’m not an electrical engineer so I am reluctant to drop the cash if it won’t work…

    Also wondering if those eglide goodyear tires I’ve seen for sale would work on an exkate.

    In case anyone is bored, I videoed riding the thing around Miami Beach:

    http://www.youtube.com/watch?v=tMWInErmmrg

    Ara

  148. Joe Says:

    @Cirujano

    While I’ve never done the conversion on an electric skateboard, I have a lot of experience working with the technology in high-current R/C applications.

    In my experiences with high current transients, you will want to use a configuration that has some caps in it to buffer the output voltage. You would have a set of cells in series to gain the voltage you need (and caps in series to match that voltage) then combine each of the series ‘packs’ in parallel to reach the desired storage (or budget).

    On the fuel cell powered go-kart I am working on, we are using maxwell boostcaps which are 2700 farads each (yes, farads). at 2.5 volts. It goes without saying these aren’t sold at radioshack.

    In case you did not already know, these cells require specialized charging as well. Don’t use the SLA charger or else you will end up with dead cells (or a out of control wicked fire if using lithium-polymer).

    Now that I’ve seen these skateboards, I want one. I think I’m going to ditch the SLA’s from the get-go and working on a direct-methanol fuel cell/LiFePO4/ultra-cap hybrid.

    Unrelated, with the whole horsepower/horse/squirell, one horsepower is the same as lifting 1 pound, 33,000 feet in one minute. Take from it what you will.

  149. Russell Dovey Says:

    I find it fascinating that you are worrying about the magnapoon and the cool spokewheels, when there is one even more glaring difference between your plank and YTs.

    Hers wasn’t motorised. The spokewheels would need power, of course, as well as the speedo and the sonic cannon, but she got all her speed from pooning passing fools in cars, after the initial footpush.

    I grieve that I cannot (yet!) share in this electric skateboard craze, since at 135 kg I am well above the max weight.

  150. Cesium Says:

    ‘Also; did today’s comic make anyone else think of “Poisoning Pigeons in the Park”?’
    Only it’s Poisoning Pigeons in a 60-square-km area of France and Switzerland. And instead of cyanide, it’s peanuts coated in… antimatter?

  151. Cora Says:

    so, I think I feel a “404 - Not Found” comic coming up. since it will be the 404th comic and all.

  152. legal hacker Says:

    There was a question going like “do they sell to australia”…

    Didn’t bother to read all the comments, so sorry if I’ve been ninjad on that before. but Taylor said: “Mention xkcd - get free shipping”.

    No restrictions whatsoever on where shipping should go.

    If enough australians order, they’ll be forced to put up an australian dependance :D

  153. stephen Says:

    not to be immature or anything, but the drawing looks like two dudes have found love.. which is okay i guess…

  154. Mr Rose Says:

    I once swore I’d never do this, but then you had to go and make the perfect comic to key it off, so nuts to that:

    “In Soviet Russia, permafrost chases you!”

    Also, is it true that all people named Randy are good at comics? Because according to my research, there’s a 1:1 correlation. Unfortunately my sample size is two.

  155. ThemePark Says:

    Regarding today’s comic: I wish I could pick up girls with that line.

    And regarding the recaptcha. Mr Generosity. Well, not really, but the recaptcha seems to like me.

  156. top2-percent Says:

    Wait a second, wouldn’t those two guys be considered clones of eachother?
    If all the purpose they both serve is to demonstrate a graphical representation of the above blog…
    Then if they have sex, it won’t be gay, it’ll be masterbation!

  157. JamesB Says:

    You, sir, are brilliant. I must say, attempting to re-create some of the adventures you describe in your webcomic is often more fun than the adventures I concoct myself.

    If you write a book, please give me the opportunity to have you sign a copy for me.

  158. Geordi Says:

    http://www.youtube.com/watch?v=ONnIjTQ_YK0

    dont know if you’ve seen this but i thought of you

  159. Shawn Says:

    An interesting april fools day joke, switching the websites like that, had me thinking my browser was messed up for a bit :D

  160. z Says:

    i was mildly confused for a bit, read the last ten or so ‘questionable content’s, thought, “well fuck. now i have a new way to use up tons of time. i think i’m going to have to go read a bunch of these.” and then it occurred to me what day it was.

    clever trick, mr. munroe. once again, i salute you.

  161. Didymus Says:

    Cleverly awesome. Though it is amusing clicking the links going between the three of y’all I know who swapped server addresses or whatever (no one correct me, I’ll ask my brother who’s a computer science major).

  162. Ghede Says:

    AHHHHHHHHHHHHHHHHHHHHHHHH!

    verynightE U wonk sha bene tnurde supide wond! HAAAAAAAAAAAAAA!

  163. ThemePark Says:

    Funny, I knew after going to qwantz, that you had sent us on a wild goose chase. I just never realized until just now reading the comments, that it was your April Fools Day joke. Well, consider me a fool. But well done.

    I actually figured initially that you had a few other domains registered and just had set them up with some front pages but with no actual content. Never occurred to me that you have just switched domains with a couple of other web comics.

    Recaptcha: the kicker.

  164. Chael Says:

    Noice jorb.

  165. Becky Says:

    My roommate early this morning: “I can’t get to questionable content! It goes to some other website.”

    Me a few minutes ago: “I can’t get to xkcd! It goes to QC! . . . Wait a minute. This is too weird. Google will know. Google knows all. . . . HA it’s April 1st!”

    Nice joke. :-)

  166. noname Says:

    hey what happen with the site?!?!?

  167. Joseph Says:

    Hello. Can someone explain to me the irritating American habit of putting the month first on the short date? I know you say, for example, “December 25th” instead of “25th of December”, like we do here in Britain but wouldn’t it make more sense to go from largest to smallest with regards to days, months and years?
    In short, 14th of March is not Pi day.

  168. Lyndi Says:

    Happy APRIL FOOLS Day! ;)

  169. Cesium Says:

    Joseph: I believe, beyond the tradition part, it’s slightly shorter to say March 14 than 14th of March, while 14(th) March is perhaps slightly more ambiguous. The year is then tacked on. In the end, though, it’s mostly tradition, which has little to do with common sense.

    “Google will know. Google knows all. . . . HA it’s April 1st!”
    And Gmail knows it doesn’t have to be April 1st. ;)

  170. Cesium Says:

    Also, there is no 31st of April, so it would have to be the 3rd of January, which is rather silly. Since you brought up the point of having the parts in order of magnitude, shouldn’t the month correspond to the integer part?

  171. Elyse Says:

    Every day, I check xkcd and questionable content. I have xkcd bookmarked and i’m too lazy to bookmark qc as well… and since there’s a link to qc on the xkcd page, it’s sort of like one-stop shopping. sort of. on tuesdays and thursdays i skip directly to the link at the bottom of the page to get my qc fix, since the xkcd is old. so today when i clicked on the xkcd link and was taken directly to qc, it actually saved me a step. so thanks for that. :D pretty nifty prank, i have to say.

  172. Domenic Says:

    Joseph: international standardized date format is YYYY-MM-DD. Too lazy to find the ISO/RFC numbers for you, but they exist.

  173. Dave Says:

    Just realised that http://www.xkcd.com/404/ 404’s
    ah the small pleasures in life :)

  174. Komrade Says:

    Haha, nifty. But I caught your silly prank, I just followed the line of sites. Wish it was longer though. ^_^

  175. Phoenix Says:

    At first I just thought I clicked the wrong link in my bookmark foloder since i read all 3 but soon found out I was very wrong.

  176. Ghede Says:

    Glee! The ending of that little slice of continuity, and a magma level burn. I’m better at it than you, my ass.

  177. ThemePark Says:

    Pwn D2-D4 and Checkmate! Although I still think the girl is the better pwner.

    And recaptcha: Joseph converted. Why and from what and to what?

  178. John Chew Says:

    I snorted admiringly when I saw that today’s comic was #405.

  179. sd Says:

    it?s such a blunt shock to find people who still haven?t converted to metric.

    It’s a blunter shock to find people who object to two male stick figures kissing. (Or who pronounce it to be “okay I guess.”)

  180. Christopher Says:

    April 1st
    Yeah, I think there was a moment of confusion,
    but then I did realize it was 1 April 2008 (another way to post dates, for those of you who care).

    404
    I see that you skipped comic #404 … will you come back to it at a later date, when we’re unsuspecting, and strike with certain fury??? Who knows … the SHADOW knows! (ten points to whomever knows the reference)

    hat
    Wow … I literally Laughed Out Loud (LOL, for those of you who’ve already forgotten the full version) … amazing that he finally caught up with her. :D

  181. Christopher Says:

    journal (again)
    Okay, so another revelation has come to me … the first one I referred to was actually journal number two - somehow, I didn’t make the connection with journal number one, but I went back and found it … and wow, that makes it even better. :D

    I’m gonna morph the three pictures into one, and use them as a desktop image, woO!

  182. Christopher Says:

    view the mastery of my mspaint skillz …
    http://ck.podzone.net/pics/xkcd.png

    messy desktop scheduled to be cleaned up in approximately … erggg … calculation error; default to “some day eventually”

  183. Nico Says:

    The shadow. It’s this movie with Aleck Baldwin (sorry if misspelled).He saves people and ask in exchange that they help him whenever he needs it. He got this mind control ability and it seems he doesn’t only use it on his foes but on people he saved too. They are too willing to risk their lives for him for this to be normal.

  184. CrackMonkey74 Says:

    hai guise! todays comic pwns.

    so why hasnt Summer Glau posted here yet?

  185. Grace Says:

    Wouldn’t the guy just be dragged off by the mini-horse; with the board just zooming off in the opposite direction?

  186. John Connor Says:

    Because, she’s got better things to do.

  187. Cesium Says:

    Grace: You’d be surprised at the friction coefficient on the board.

  188. ThemePark Says:

    Cesium Says: “Grace: You’d be surprised at the friction coefficient on the board.”

    That’s what SHE said.

  189. Jenni Robinson Says:

    I am sadly lacking a witty comment to reply to this posting, but I just had to say (and I’m quite sure you get this daily) if I bake for you, will you marry me? I may not be a science major, but I have a degree in baking and pastry- and I can cook, too. :p lol. Keep it up, I love reading your stuff.

  190. Vladimir Roschjenko Says:
  191. Vladimir Roschjenko Says:

    Randall is a faggot.
    Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.
    Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.
    Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.Randall is a faggot.

  192. Cesium Says:

    Randall is a stick of wood? What?

  193. Jenni Robinson Says:

    Very smart wood.

  194. Rashkavar Says:

    Regarding the squirrel lifter: if that thing is operating on the electromagnetic levitation concept (which I believe is the only known practical way to do that with current technology), then….you’re COOKING THE SQUIRREL!!!!!!!!!

  195. Mac Says:

    This is incredibly off-topic…

    I attempted to email admin@limerickdb.com from two different accounts, they both bounced. If it’s a fake email to protect yourself from idiots like me… it’s working.

  196. deadcellplus Says:

    can we plz have Vladimir Roschjenko’s email?

  197. Drithaan Says:

    Death by rabid xkcd fan flame attacks. That seems a just punishment to me.

  198. Christopher Says:

    So I was recently informed as to what “that’s what she said” means. (isn’t that what SHE said?)

    Anyway … Vlad seems to be a very clever individual who has the most original material evar!
    That said, I’ve never seen someone who looks like a cigarette, OR a piece of wood. Nor British meatballs.
    That said, I believe his email is vlad_adores_randall@hotmale.com

    This is a comment of the 1AM variety … forgive the insanity, please.

  199. Drithaan Says:

    Death by having to see myself in the mirror every morning: Priceless.

  200. Drithaan Says:

    NINJA’d!!!!!!!!!

  201. ChrisM Says:

    Thought I’d find an Easter Egg on your site, when I noticed your recent strips skipped from 403 to 405. Manually entered URL. … … Finally remembered that 404 had some kind of importance as a number in its own right :)

    PS Have you considered installing some sort of ’subscribe to comments’ plugin for this wordpress blog?

  202. ZMTToxics Says:

    I am surprised you drew that as a horse versus 600watts and the horse loosing.

    1 Kilowatt (1000 watts) is 1 Horse Power. In context with the blag comic, the horse should have one being 400 watts more powerful. :D

  203. Anonymous Says:

    But 1 hp = 745.699872 watts

  204. Cesium Says:

    It’s anywhere from 735 to 746. Also 9809 o_O

  205. Drithaan Says:

    Noes! They be stealing my name!

  206. Random Person Says:

    This comment might seem random, but I don’t know… Who’s Paul Erd?s, other than he’s some hungarian guy?

  207. Arancaytar Says:

    Famous mathematician. He got picked him as an arbitrary “root” node of the social network of mathematicians - hence the “Erdös number” that measures your distance to him in co-authored papers.

    Erdös has an Erdös number of 0. Everyone who co-authored a scientific paper with him has an Erdös number of 1. Everyone who co-authored a paper with one of those has a number of 2, and so forth.

    He’s dead now, so no one can score a 1, but if you hurry up you can still get a 2. :)

  208. Cesium Says:

    Often compared to the Kevin Bacon number.

  209. andrew fowler Says:

    hey, does someone want to mail me the engineering concerns with the spoke wheels?

  210. Hugh Says:

    Of course, 1 horsepower is actually calculated as 150% more than the average extended power output of a welsh pit-pony working mining machinery. An average sustainable power output of a larger horse is more like 80% of a horsepower. However, a horse’s peak output can be as much as 20horsepower. Subsequently I would suggest caution when attempting to compete a small horse in a tug of war.
    But seriously, sweet board, and I loved the comic.

  211. Shridhar Jayanthi Says:

    Sir, the last comic with Calvin & Hobbes is just pure evil genius. You should be awarded some comic prize for that. Really.

  212. Charles Shapiro Says:

    I just bought one of these electrical skateboard thingies on EBay. A raptor 4 as it turns out.

    So far it feels like a solution without a problem. I can go way faster & further on a bike, and cargo capacity is about the same. Plus, yomping 50 lbs of batteries and motor through the public transit system here is insanely hard. But heck, it’s an amusing toy. Playing around with it is more fun if you have a group.

  213. Rebecca Ogle Says:

    Today’s double comic is so win I could kiss you. I could. Right through my screen, from Maryland to Boston, all Ringu on your ass but with kissing instead of killing and no wells ’cause I’ve never been in one of those and don’t particularly want to try it.

    So win.

    Also, rock on with the latest blog post about movie heroines. You figured out the secret: feminism + Calvin & Hobbes = awesome fangirls.

  214. Altoid77 Says:

    without even seeing the last frame, i knew it was a calvin & hobbes comic — kudos to you, sir. :)

    …and I totally have to agree with Rebecca on her last sentence. Carry on.

  215. Y.T. Says:

    Race you to River Gods :)

  216. Greg Says:

    Please note:

    “Girls will talk to you”

    http://boston.craigslist.org/gbs/mcy/639131492.html

  217. OMG » ?????! Says:

    [...] ???, ??? ????? ?? ??????? ??? ?? ???? ?? ????? ?????? ????, ??? ??????. ?? ?? ?????? ?????? ?????? (???? ??????? ???????? ?? ??????? ????? ???????? ????? ??? ?????) ??????? ????? ??? ?????. [...]

  218. Cesium Says:

    Hunh… Hebrew pingback.

  219. gregory Says:

    You should of definitely gotten a wheelman instead. No battery costs to worry about, amazing gas efficiency, quick ‘recharges’, ATV capabilities and you can use it like a snowboard.

  220. Rachel Says:

    March 14, 1592

  221. Cesium Says:

    Even better, 3:14:15, Sept. 26, 535

  222. Vincent CLEMENT Says:

    Hello I am Vincent, in a internship in a Mechanical and Industrial Company called Fish4Parts in Salford, Greater Manchester, Uk.
    We supply many companies needs.
    Besides, perhaps yours in the future.
    Best Regards

    http://fish4parts.co.uk

  223. liryon.liquidorange.net » Blog Archive » ROFLCon Friday Says:

    [...] few blocks of me, but I’ve never seen him in the grocery store or walking to the T, or on his electric skateboard. But tonight, with ROFLCon in town I saw him, and a large posse, including Ryan North on my walk [...]

  224. liryon.liquidorange.net » Blog Archive » ROFLCOn Friday Night Says:

    [...] few blocks of me, but I’ve never seen him in the grocery store or walking to the T, or on his electric skateboard. But tonight, with ROFLCon in town I saw him, and a large posse, including Ryan North on my walk [...]

  225. MM675 Says:

    MM675…

    Not sure how these mowers will hold up. So far they’ve been saving me money….

  226. Sally Rhodes Says:

    Wow, I feel ridiculously stupid. In the first picture, I misread “600 watts” as “goo waits.” Then I started picturing it- some guy who’s really excited about his new electric skateboard, accidentally landing in a giant pile of goo. How tragic.
    Thank you for making me laugh incredibly hard :-)

  227. ankara evden eve nakliyat Says:

    very nice article.

  228. I SKATE. Says:

    hey, this is why americans are taking away from the sport and being a bunch of lazy assholes. If you cant ride a skateboard, then that sucks for you. dont be fat and get an electic one.

  229. Jesus Says:

    Yeah screw innovation, we should all walk…..barefooted…. everywhere…

    On a more serious note, I just got off of the telephone with Exkate and they are out of the 600 and 800 series boards until……..August. Seriously WTF mate.

    Anyone have a good alternative?

  230. Kaitlyn Says:

    I have possibly the best idea for a comic ever
    and you should do it.
    Well, it’s really not the best idea ever, elevators was a better idea, but I still want you to do it.

    Pulling a horse with a car would be fun (for relevance).