Electric trials bike build

Discussion in 'Observed Trials Discussion' started by Denisesewa, Dec 25, 2012.

  1. Denisesewa

    Denisesewa Member

    246
    0
    16
    For the past month I've been working on building an electric trials bike with the idea of having something which is trail and trials ridable as well as still being able to be peddled, things are coming together and the bike is impressive although I still have some work to do in getting the low speed power delivery into a more controllable state, as it sits now the intitial torque is abrupt and at times scary, I am going to have to buy a different throttle, the one I have is just over 1/8 turn from full off to full on. not having a clutch or engine sound is also going to take a different style of riding, but its a blast to trail ride.
    So, I started with a Jackflash.
    [​IMG]

    Switched the rear wheel to a 24" downhill wheel with a 24x3.00 tire, installed a boxxer fork and have it set up as a 3 speed using a 9 speed cassette and X-9 derailiur with a X-9 3 speed shifter, this setup shifts 2 cogs at once and works perfectly, I also set up the speed controll to have 2 power settings by flipping a switch near the throttle, I am still experimenting with different programming for the power settings to help calm down the torque.

    [​IMG]
    I fabricated the battery compartment from aluminum and the bodywork and fenders from glass and carbonfiber along with a hell of alot of work and fabrication for the drivetrain.
    [​IMG]

    [​IMG]
    The bodywork was time consumming but in the end I achieved the look as was after which is to have the bike look clean and uncluttered, still resemble a bicycle but have a very mototrials flavor, the seat is teloscopic and can be raised to a comfortable height to peddle if needed.

    [​IMG]
    [​IMG]
    [​IMG]
    [​IMG]

    I dubbed the bike " Pedatrial AGB" ( Anti Gravity bike) since downhill bikes are known as Gravity bikes I thought this was appropriate.

    [​IMG]

    [​IMG]

    I got out for a ride yesterday and took some video, the video is raw, kinda crappy and uncut and with the fisheye lens it doesnt really show just how steep some of the terrain is, I can say that I cant make alot of this on my mountain bike and its steep enough to be difficult to hike a bike up, the pedatrial just ate it up and I now know I can gear it up since I never used low gear.at one point around 8.30 in the vid you can see where the twitchy throttle caught me off guard.
    [ame]http://www.youtube.com/watch?v=HQSFbLXzsNo[/ame]

    Lots of work and tinkering left to do but the potential is there and I am really happy with the result so far.
     

  2. treewizzard

    treewizzard draquella is back!

    4,178
    0
    0
  3. AnthonyRev3

    AnthonyRev3 New Member

    463
    0
    0
    Awesome
     
  4. trials-online

    trials-online still here

    1,524
    8
    38
    pedatrial sounds a lot like pedofile ... just saying! cool build though!!!
     
  5. Denisesewa

    Denisesewa Member

    246
    0
    16
    Yeah, I made the comment on the electric bike forums that I would probably now be known around town as a Pedatrial. Its all in good fun.
     
  6. AnthonyRev3

    AnthonyRev3 New Member

    463
    0
    0
    Have you thought of powered hubs? Front wheel drive....
     
  7. Denisesewa

    Denisesewa Member

    246
    0
    16
    The hub motors are pretty gutless at the same voltage and wattage, they are fine for commuter bikes and I dont want the extra weight up front. the system on my bike is a very high rpm motor with double reduction and allows the use of shifting gears on the final drive which means high torque with the abilty to still have some speed and still be very battery effecient .
    two wheel drive would be interesting though.
     
  8. AnthonyRev3

    AnthonyRev3 New Member

    463
    0
    0
    I seen one on youtube that looked pretty sick. 2 wheel drive. 48 volts. Always wanted to have an electric bike. You bastard lol.

    Beta's are the best. Gasgas is ok.
     
  9. Denisesewa

    Denisesewa Member

    246
    0
    16
    I wasn't all that impressed with my beta techno, thought it was kinda clunky but I never rode a Rev.
    If you look at the pics my bike says "no" gas gas, get it?
    If you want to build one go to Endlessspere.com, tons of info there and some really cool builds.
     
  10. pkb4112

    pkb4112 mOd N0ob

    683
    0
    16
    Super cool. It shows how much work you put into it, looks awesome.
     
  11. Blackstick

    Blackstick Well-Known Member

    2,089
    244
    63
    I can't even imagine what it would be like to have that much spare time. I'm hugely jealous.

    I'm also impressed, very cool looking rig.
     
  12. Juhan

    Juhan Welcome to Estonia.

    785
    33
    0
  13. Denisesewa

    Denisesewa Member

    246
    0
    16
  14. tooold4this

    tooold4this but in denial

    449
    2
    18
    Good looking body work! I need to learn how to do a bit of that, nicely done and looks like fun!
     
  15. Alan4505

    Alan4505 Engineer the future NOW.

    329
    0
    16
    Very nice work. Curious about the motor/drive-train/battery parts. Care to elaborate?
     
  16. Denisesewa

    Denisesewa Member

    246
    0
    16
    Its a " GNG Mid drive Brushless motor" system and can be purchased on Ebay although I modified mine with a programable controller and I converted the primary belt drive to chain since the belt has proven to be unreliable, it is a double reduction system with two freewheels to keep the pedals from turning while under power and so you are not turning the motor when you peddle with the power off.
    I built the battery pack from 5000 Mah Turnigy Li-poly cells 14 in series x 2 Parallel for a total of 10,000 Mah at 52 volts nominal( 58 volts hot off the charger), the motor is capable of 2000 + watts, its advertised at the usa street legal limit of 450 watts.
    I have the new controller set at 30 amps and block timing allows spikes up to 38 amps so its actualy putting out 2744 watts during the spikes which is about 3.67 HP , doesn't sound like much but the torque is impressive and the motor is just warm to the touch after hard riding.
    There is a long thread on this system here >> http://endless-sphere.com/forums/viewtopic.php?f=28&t=42785 with links to several builds and video , Check out BZwindtalker's for some vid of his at just 22 amps ( basicaly stock system) and Christrlung's bike at 72 volts.
    Is that enough info?
     
  17. Dabbil

    Dabbil New Member

    53
    0
    0
    http://holmeshobbies.com/

    The guy that ownes that website has an electric MTB that does about 45mph with a hub motor.

    Guy does amazing stuff with electric motors. He might be able to help get a little more out of your electric motor.
     
  18. Denisesewa

    Denisesewa Member

    246
    0
    16
    Hey Chris,
    The glass work isnt difficult but is a bit time consuming. I did a little tutorial a few years ago, I'll have to see if I can find it.
    I'm thinking this will be a great spectator bike at some of next years moto events, going to have to try to get out to a few of those.

    Dabbil wrote >http://holmeshobbies.com/

    The guy that ownes that website has an electric MTB that does about 45mph with a hub motor.

    Guy does amazing stuff with electric motors. He might be able to help get a little more out of your electric motor. "

    I am actually happy with my power to effeciency ratio, I dont think I'd want more power at the cost of run time. Thanks though!
     
  19. Ramrod

    Ramrod My body is ready.

    5,468
    8
    38
    Sorry a bit off topic, but I was looking at a 22.3 horsepower (690cc) horizontal axle small engine back in the day thinking how easy it would be to mount behind the seat (on a rack) on a cheap re-enforced steel frame.

    I'm wondering what kind of speeds I could achieve, and what kind of issues I would run into mechanically.

    My plan was to remove the whole bottom bracket, cranks and pedals, then replace them with foot pegs like a motorcycle. No pedaling.

    A motorcycle chain would run directly from the axle shaft straight down towards the rear wheel, and I would run a wire along the frame to my handlebars for throttle.

    The weight of the engine would increase traction on the rear wheel.

    Simple, powerful and fast...or is this something that can't happen

    My goal is to go as fast as hell.
     

    Attached Files:

    Last edited: Dec 27, 2012