2007 Yamaha Drive Abrupt Throttle Response

[tomtt2]

I recently purchased a Yamaha Drive with a high speed motor installed. The cart runs well and tops out at just over 25 mph. The only complaint I have is that the throttle pedal response is very abrupt.

Specifically, for the first 1/3 or so of pedal movement, there is no response from the motor. Then, the cart suddenly reacts as if the pedal was floored (no smooth linear response to the pedal movement). The real concern is backing up. The lunging of the cart is close to dangerous.

Isn't there some way to change the voltage supply curve from the controller to the motor so that the response is smoother? I was told that the cause of the problem is the high-speed motor, but that doesn't explain the abrupt throttle response.

Any ideas or suggestions for improving this situation?

Thanks for any input.

[smallblock450sl]

Originally Posted by tomtt2

I recently purchased a Yamaha Drive with a high speed motor installed. The cart runs well and tops out at just over 25 mph. The only complaint I have is that the throttle pedal response is very abrupt.

Specifically, for the first 1/3 or so of pedal movement, there is no response from the motor. Then, the cart suddenly reacts as if the pedal was floored (no smooth linear response to the pedal movement). The real concern is backing up. The lunging of the cart is close to dangerous.

Isn't there some way to change the voltage supply curve from the controller to the motor so that the response is smoother? I was told that the cause of the problem is the high-speed motor, but that doesn't explain the abrupt throttle response.

Any ideas or suggestions for improving this situation?

Thanks for any input.

You'll need to take the floor mat rivets and floormat (from the driverside) and move it to the passangerside and remove the pedals assy acsess panel. Look to see if the accelerator pedal moves before actuating the shaft that moves the "TPI" (throttle position sensor). Disconnect the TPI from the main wire harness and check for corossion (sometimes you can use electrical contact cleaner and then use some "dyalectric grease" to solve the problem). If not I can get you ohm readings to test the TPI. There is no way to change the voltage supply curve that I know of. Lastly, the high speed motor could have caused damage to the very low rated stock Yamaha MCU/controller, there only rated at like 260 amps. Let us know what your findings are.