How do I By Pass the electric controller ??

Discussion in 'Electric Bicycles' started by will_start, Oct 20, 2008.

  1. will_start

    will_start Member

    Hi All,

    I recently purchased an electric bike:
    See here for pics and details of the website.

    I was told by the shop guy that its possible to bypass the speed controller.
    To increase the max speed of the bike from 26km/hr up to like 50km/hr.

    How would I safely do this is what I'd like to know ??

    Safely being, as far as not affecting the warranty on the bike.
    Safely being, how to not affect the longevity of the motor.

    Any input gladly taken. I've searched for the details
    of the bike online, but couldn't find them.

    I'm happy to look further inside the bikes electrics if needed.

    I'd rather not ask the shop guy, as he put his job on the line
    by telling me in the first place.

  2. ozzyu812

    ozzyu812 Member

    Without seeing it it s hard to say exactly what to do.
    Maybe someone at has that model and has done it.

    200w limit in AU. I used to want to move there. LOL
    If I was there I'd have more powerful parts imported. Then gut that bike and start over. Do they have watt sniffing dogs at customs?
    Last edited: Oct 22, 2008
  3. will_start

    will_start Member

    Hey Ozzy,

    Thanks for the reply.
    I'll search that site. I did buy a 1500W bike before, which had some issues,
    whilst not legal here, there are no Wattage Dogs on the road.

    The only issue with going over the wattage, is if you have an at your fault accident, then insurance won't pay you anything, as you were doing
    something illegal. (thats my view, right or wrong).

    I'll have to open up the cover and see if there's a model on the circuit board.

    The guy at the bike shop said, "Its on the Internet..."
  4. skyl4rk

    skyl4rk Guest

    You probably need to buy a new controller. He may have been talking about connecting the batteries directly to the motor, but thats not really practical.
  5. will_start

    will_start Member

    Hey Skyl4rk,

    I think you're right, he said you can use some relays to bypass the controller.

    Why is it not practical ?
    Will it burn out the motor.

    The bike does hit its top speed of 26km/hr then the motor cuts out.
    I know its got more in there, I'd love to get to 40km/hr,
    but not at the expense of the motor...
  6. skyl4rk

    skyl4rk Guest

    If you put a switch in parallel with the controller on the positive wire, to bypass the controller, you might be able to get more speed. Will it burn out your motor? Possibly. However if you are going more than 10 miles per hour it will probably be ok. Don't bypass while standing still or moving slow and you will reduce the risk of motor or controller damage.
  7. will_start

    will_start Member

    Hey Sky,

    Ok, that's the start of a plan. Seems like the risk is not worth the benefit.
    It also seems like a controller is needed that will do what you describe,
    as the switch idea is not practical for riding.

    any idea where i could get a controller that will turn on at a set speed ?
  8. Ypedal

    Ypedal Member

    First thing you need to figure out is if it's a " Brushed " or a " Brushless " motor.

    If it's BRUSHED : the motor will only have 2 wires, + and - , hook these babies up to a battery directly and away she goes.. reverse the polarity and it goes in reverse.

    If it's BrushLESS : You absolutely need a controller. The wires that exit the motor will be 3 x thicker wires and 5 more " Hall " position sensor wires.. 3 wires means you can't just use 2 on + and -.. it requires electronicly controlled timing only possible with a controller.

    Both motors.. will spin faster if you add more voltage, ( More batteries in series ) .. Voltage = RPM

    If you hook up a Brushed motor direct to a battery , with a simple ON / Off switch, the motor will suck as many amps as possible to try and get up to cruising speed.. this will drain your battery FAST if you flip the switch when you are going slow, it will heat up the motor, wear the brushes faster, and all that fun stuff.. possible.. not advisable.

    Either way, you can get a higher voltage controller for both brushed and brushless motors... but lets start with what motor you got.

    Report back.
  9. will_start

    will_start Member

    Hey YPedal,

    Thanks for the answer:

    Here's the web details on the bike:
    It says its Brushless.
    200W High Efficiency Brushless Motor.

    I only travel short-distances at the moment, under 10km.
    So battery life is not that big a deal.

    Whats the next step ?
  10. Ypedal

    Ypedal Member

    Stock 36v.. hmm..

    Most. and i repeat.. " most " 36v brushless controllers will survive at 48v, this means simply adding a 12v in series ( you also need a 12v charger for the extra battery ) . Crystalyte controllers can handle this.. so do wilderness energy.

    Does the throttle have an " LED " status light ? ( it will not display correctly at 48v if you have an led throttle .. you can snip the led wire to disable it )

    Can you locate the controller on the bike ? ( black box.. or silver. ) any model number.. stickers of any sorts etc.. ?

    Does the motor have any markings ?
  11. will_start

    will_start Member

    I'll check it out.
    and see if I can find model info,
    and report back.

    The motor is silver, and has a 26 on it.
    inside a green dot. No model is printed on it.

    The controller is either in the front of the bike,
    or located in the under-neath housing, next to the pedals.

    I'll have to take it apart to see if there is model info,
    I may be able to do this on Sunday.

    Ok, I spoke to the guy at the company who makes them.
    And he said its not possible to make it go faster,
    as its illegal to do so, as you'd need more power than the legal limit.

    Australia has a 200 W limit on the power of a bicylce.

    So I understand his point, as I could be an under-cover
    police officer, asking if they would do something illegal.

    That said, I get over-taken by "proper cyclist's" on a regular basis.

    I want more speed, however.
    Last edited: Oct 23, 2008
  12. skyl4rk

    skyl4rk Guest

    Sorry about the bad info, I was thinking brushed motor.
  13. will_start

    will_start Member

    You had me excited for a while there, and actually considering
    I may get a speed increase.

    Oh well, its what happens when you live in a Nanny State
    like Australia.
  14. skyl4rk

    skyl4rk Guest

    Try more volts!
  15. will_start

    will_start Member

    yeah thanks for that bit of rocket science :-/
  16. skyl4rk

    skyl4rk Guest


    more like mad scientist science!

    Seriously, If you want to go faster with the bike you have, you will have to increase the voltage. Will it break the controller or motor? Possibly. Your best bet is to find out if someone has tried it and how long has their system lasted without blowing up. Somebody has to take a chance to see if it will work. If you don't want to risk anything, leave it the way it is.

    These systems can last a long time, but if the motors get too hot or a capacitor or mosfet in the controller pops due to overvoltage, you have just proved that you are running over what the system can handle.

    I guess I should not have posted originally because I don't know anything about your system and actually gave you bad information at first (by mistake, sorry). However I was hoping to help you or at least guide you in the right direction to get the info you need.
  17. bgmiller

    bgmiller New Member

    Bypassing the controller

    The purpose of a speed controller is not to limit the amount of electricity to the motor but to use only the amount you need to run the motor. Otherwise a rheostat will work, but with a rheostat you are using the same amount of electricity at low speeds as you are at high speeds, with the rheostat using the difference to create heat. Almost like a element in a heater. If you really want to bypass the controller, just hook the battery direct to the motor and use a toggle switch. Of course you will be running full power to the motor anytime the toggle switch is on.I did once take an electronics course back when they were still using vacuum tubes.
  18. will_start

    will_start Member

    I have no tinker time, and don't want to risk the warranty I have.
  19. AussieJester

    AussieJester Member

    So why make this thread in the first place... you have to do both to achieve what you asked in the OP.

  20. will_start

    will_start Member

    Tinkering times ?

    KJ, I really like the results of your Tinker time.

    I used to have Tinker Time, 8 months ago when I started this thread.
    But that was before I broke up with my Live-In Girl-friend and had to move 70km away from work, at my owner occupier home.
    So, I now commute 3 hours a day or 15 hours a week, leave home 6am, get home 7pm, as opposed to a 25min bicyle ride to work.

    And there is no option here to close threads !!
    So some fool digs em up 6 months down the track,
    for you to comment on something you've moved on from.

    kapish ?