motor + controller for motocross bike

[Rouckie]

Hello all,

I'm searching for advice in regards to a motor + controller to build a motocross bike.

some background:
I tested a ktm freeride e last weekend and have found it to be a good alternative for a 4 stroke motocross bike, if the track is not too fast. The ktm has a peak power of 16kWatt (but continuous) and this is enough for me. Only the price is pretty high at €11.000.

so, the idea is to build a motocross bike myself. I'm looking for a motor + controller that can rival with the ktm motor. It can be a bit less powerfull as well, the 16kWatt is the benchmark. I will use a 2 speed transmission, so I believe I can get the same performance with a less powerfull motor. You can feel the power drop with the ktm above 50km/hr...

I was thinking about a golden motor HPM10k motor with corresponding controller. Is this a good idea? up to the task?
another candidate is the adaptto e-max controller, with a outrunner rc motor.

thank you very much for the advice,

Roel

 

[DanGT86]

That ktm is pretty impressive goal to strive for out of a diy bike. What is your intended budget? Do you have access to machining and fabrication equipment? These factors may determine what route you go.

ES member Liveforphysics has tested those golden motors and had this to say about them.
http://endless-sphere.com/forums/viewtopic.php?f=30&t=63071&start=25

A few members have experimented with RC motors coupled to 2stroke motorcycle gearboxes and have had good results. I think having a gearbox would make it easier to keep an RC motor alive without overheating it or the controller.
http://endless-sphere.com/forums/viewtopic.php?f=28&t=57579

Member recumpence builds 30kw RC powered bikes without using a multi speed gearbox but that is using very nice Astroflight motors commonly fan cooled and with torque limiting clutches. These bikes are far above average diy quality and are great examples of how capable the RC motors are in a properly designed system.
http://endless-sphere.com/forums/viewtopic.php?f=28&t=65549

One more option for motor and controller would be a Hubmonster or Midmonster from ES member John in CR. These are scooter motors but with the wheel flanges cut off of them they can be used like a large outrunner. They are basically 2 3phase motors in one case so they require 2 controllers but the controllers can be inexpensive common ebike controllers. John in CR has been using these motors well into motorcycle power territory with good results. I think this is about the best power/cost setup and would be mechanically simple to build because the high torque of these motors likely wouldn't require a gearbox.
http://endless-sphere.com/forums/viewtopic.php?f=31&t=46898

I wish i could give you a recommendation from personal experience but I haven't had the money or time to build something at motorcycle power yet.

Good luck.