Throttle Sensor Assy

[backhoe1]

can any one tell me about the THROTTLE SENSOR ASSY on my 2001 yz 426 what can the bike do if it don't work

[Ga426owner]

can any one tell me about the THROTTLE SENSOR ASSY on my 2001 yz 426

too vague...what do you need to know about it?

part number..

how it works...

what it looks like...

if it is broken...

[backhoe1]

Throttle Sensor Assy

if it is broken...how it works...

[grayracer513]

Depends what you mean by "broken".

Its function is to increase ignition advance for lighter throttle openings at any given engine speed to improve combustion efficiency, and retard it at heavier throttle to avoid pre-ignition.

If it fails so that it is an open circuit, as if it were unplugged, the CDI defaults to full throttle timing at all times, and controls the timing based only on engine speed.

When it gets ugly is when the TPS output voltage varies erratically as the throttle opens instead of tapering smoothly from high to low. That causes the timing to move around, spiking and dipping in response, which can cause a variety of odd behaviors. If you suspect this, unplug it and try the bike then. If it seems to correct the problem, test the TPS with a meter to see if the resistance increases smoothly as the throttle opened.