Need new motors? break a chain? brakes not work? swapping out pinions or sprockets?

Moderators: robnewyork, bassiclyLouDog, gameboy

I bought this bike local. guy said his kid got it wet and it quit working so he bought a motor for it from one of the online vendors. It has thier sticker on it...

but its apparently the 300 watt motor not the 250 they stuck in all their newer models. If not mistaken only early versions had the 300 watt motor.

anyhow. it does nothing when throttle applied. I hear the click of the controller I guess.

should it work? Or is the motor and controller not going to work? I have a YK31C controller if I need a controller..will that work? I also have a thumb controller that I bought at same time. I was going to run these parts on my E300.

I need to get it all working to sell it cause I have a MX500 I picked up as a better platform to build on. the motor is new but like I said not the original size for this version. does it matter? maybe the batteries are just shot. I will check that next
I had this problem with one of my Razor quads. If you are hearing a click when you apply the throttle then I know what the problem is. There is a relay in the controller that when energized it unhooks the motor from the controller. It may be the brake function as mentioned before or the low voltage disconnect. In my case the batteries were good. I was able to get it going without the click by pushing it wit the throttle at zero and then giving it throttle while it is moving. Anyway that is not a solution to the problem just a way to verify it. I opened up the controller and bypassed the relay. If the others on hear have other ideas to try first then that is good. I don't know your skill level. Bypassing the relay by soldering wires on the circuit board may not be something that you an do.
8mm (T8F) rear wheel sprocket

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