Electric motocross bike build to Oset frame

[redline2097]

I am building my kid mx bike on a Oset 12.5 frame. I considered other frames including mx bike frames but they all are way too high for my kid. I will fit 16" osets front fork and wheels to it. So it adds only 50-70mm to seat height (total 440-460mm). Also I add rebound to front and back. Only question is the motor and the controller. I want my boy to grow it with me increasing power little by little. But our goal is to go faster than 65cc bikes. So we need tons of power and torque. I can attach motor with these dimensions, 130mm diameter, 100mm depth + axle. I prefer mid drive because of balancing the weight of bike. Motor weight should be less than 5.5kgs (12 pounds).

I have been looking this combo but I am open to other more powerfull recommendations (I don't need more wattage but more torque with 150 amps would be nice)
Motor: http://www.revolt.org.il/rv-120/rv-120pro-2/
Controller: http://kellycontroller.com/kbs72221e130a24-72v-mini-brushless-dc-controller-p-1316.html

Controller size could be maximum of 160mmx120mm. Motor price should sub $500 and controller sub $400.

Any other recommendations?

 

[Sean9002]

It has been done before, Ive done a 20, and im pretty happy with it.
Here is a trials central thread on an Oset 12 build. Not sure if its a member here. I love that he removed the battery tray and went to a trellis style
http://www.trialscentral.com/forums/topic/44325-oset-125-frame-mod/

 

[redline2097]

I will remove battery tray and kickstand too for reducing the weight of bike. I have read that thread too on trialscentral.com and get the motivation from there.