Electric trail bike

Discussion in 'Some Assembly Required' started by Luke, Jul 27, 2011.

  1. Sequoia

    Sequoia Been here awhile

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    Is there a minimum distance that the batteries have to be seperated by ?
  2. Luke

    Luke GPoET&P

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    It doesn't seem like it. They barely get warm, and I doubt they would overheat even if packed tight. I'd assume that wouldn't hold for all sorts of bikes or batteries, though.
  3. knary

    knary sunshine and puppies

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    Is there a ready solution for modulating the initial power ?
  4. Luke

    Luke GPoET&P

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    No.

    As in, I'm working on it but it's not ready yet. :D
  5. oregoncoast

    oregoncoast Racing Like a Noob

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    Duh!
    What about making an electric vintage trials bike? Ever thought of that? :wink:
  6. MortimerSickle

    MortimerSickle Semi-Adventurer

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    <iframe width="420" height="315" src="http://www.youtube.com/embed/LYm-1ts6dqI" frameborder="0" allowfullscreen></iframe>
  7. knary

    knary sunshine and puppies

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    :D

    A couple things come to mind, but I don't know what the hell I'm talking about. :lol3
  8. rayivers

    rayivers n00b

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    Incredible job on the bike, and great thread! 8 pages and counting of high interest, helpful/supportive comments, and zero hate - ThumperTalk could sure learn a lot from this place. :>)

    I just put down an initial deposit on one of these - it's like a dream come true for me, I hope they can find 49 more people who feel the same:

    http://www.evdrive.com/prototypes/category/e-moto-crf250r/

    They're not cheap, but the KTM Freeride E and BRD's (https://www.faster-faster.com/bikes.html ) won't be either, when they finally get around to producing them.

    It'll be so cool to finally be able to just ride, and not broadcast.

    Ray
  9. dentvet

    dentvet Long timer

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    Anything new for MY2012?:ear
  10. rainmaker8

    rainmaker8 Been here awhile

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    I've been toying with the idea of building my own electric moto. Even got a spare rolling chassis waiting...
    But it's a slightly larger frame intended to perhaps hold more battery packs and potentially hit the road for dual sports but longer range is like the electric vehicle holy grail... there's always a weight and cost compromise!

    How are you dealing with the waterproofing?
    I noticed you tiptoed around those mud puddles last year in the video...
    Obviously the controllers and such need protection, but what about the motor?
    Is a brushed motor more susceptible to moisture damage?

    keep up the good work!
    I'm so excited to start mine...
    :lurk

    T
  11. Luke

    Luke GPoET&P

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    As a very belated update,the YZ has its gas motor back in. Its nice how similar the handling is between the two setups. I'm not willing to add all the extra weight to get decent trail range, so I'm going to put the same electric parts in a trials chassis. The changes I made to the controller should work well for trials riding.


    The YZ had almost no water protection, it would be necessary for anything ridden off road regularly. I'd expect dust to be bad for the brushes too.
    It's fun building, good luck. If you're willing to get the bike up to DS or ADV weight then you'll get much better range.

    The CRF looks really nice. Their packaging is impressive. Two parallel motors must be awesome, hopefully it works better for them than on the Motocycz IOM bike.
  12. azcagiva

    azcagiva new orange flavor

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    Hey Luke,

    Have you checked out the forum "endless sphere"?

    I have a friend that is quite knowledgeable in the electric bike propulsion deal.

    If you want I can give you his email.

    I talked to the dude that has the electric class one buggy, he should be running it in the upcoming NORRA race.

    -John
  13. Luke

    Luke GPoET&P

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    Hi John,

    I have seen endless sphere, lots of good ideas there.

    Always good to talk to people, if you'd send me his email that'd be great. Unfortunately I've got some plans for this bike but no time to fit them it. But avoiding potential mis-steps would be really nice.

    I was thinking of trying some different cells, and now that A123 has gone bankrupt I may have no choice. :cry


    I'd love to see that buggy at the MX1k, I hope they make it.
  14. YamaGeek

    YamaGeek Ancient trailbike padwan

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    Wow Luke, very nice! wonderful documentation on what you did and the problems and solutions you came up with. E bikes are still evolving some, it's really a shock to hear that A123 has gone bankrupt, they were the cell of choice for serious big scale RC model aircraft.

    Some random thoughts from someone who's been in the RC hobby and has made a few DIY electric power systems for small model airplanes.

    The brushed motor you used , was it rare earth magnets or Ferrite? there's a bit of efficiency gains, small, but significant to using Neodym or Cobalt over Ferrite.

    A lot of what has happened in the past 12 years in RC has been the flood of cheap and relatively well designed brushless DC motors, the brushless controllers are now using a sense circuit off of the power output that detects the motor poles/magnets and synchs the controller up to the motor. They still haven't made the initial application of power on these motors smooth enough to work well for vehicles yet, ( I believe this to be true..) So the best bet for BL vehicle motors will have sensors in addition to the 3 power leads, I'm suspecting that this is what is mostly available off the shelf for brushless powered E-vehicle motors.

    Most BL motors are form of 3 phase AC synchronous using rare earth magnets, they've gotten to the point where the designs can be made to turn just about any power output and RPM needed. You're probably well versed in the variety of motors available for E-bike conversions, so don't mind me just thinking out loud.

    Have you thought of changing to a lighter form factor like a sturdy suspended MTB? You might increase the run times and not have to resort to such a large motor. Considering what you've achieved maybe the trials bike is the best compromise for weight?

    quite awesome, subscribed. :clap
  15. Luke

    Luke GPoET&P

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    I actually don't know what sort of magnets are in the motor. I just know it has lots of power for its weight.

    I avoided brushless motors because they didn't seem to offer any performance advantages and the drive system is way more complex. The complexity isn't such a big deal if you're going to stick with a puchased controller, but it is if you want to modify it like I did.