6500 RPM and it goes crazy

[maddad]

Looking for some advice/confirmation of my thoughts. Bike is working excellent after engine being pulled, freeing up the cold start valves, TBS and a good trip coast to coast and back.

But riding today as it revs up to 6000 RPM it works great and smooth. As soon as I hit 6500 it jumps around like a son of a gun. Does it in 1,2,3. Keeps jumping around but less so once about 7000 RPM. As in jumps around you can see the tack lurching between 6000 and 7000 RPM once per second.

I suspect the throttle position censor. Has anyone else seen this or can suggest a suspect part?

 

[bluesdog]

..
I suspect the throttle position censor. Has anyone else seen this or can suggest a suspect part?

Your suspicions are likely correct. That's the first thing I would get checked out. Sadly, I have no idea how to test the thing. Good luck.

 

[maddad]

You can actually test it just by putting the bike in diagnostic mode. As you rotate the throttle it will show you a reading from I think about 3 to 100. However that's when stationary and I suspect when the bike is running I'm getting vibrations that add to the bad circuit.

 

[bluesdog]

Maybe try moving the TPS sensor wires while at idle?

 

[kenporider]

I think it has more to do with load rather than vibration since it's RPM related. Mine went bad a couple of years ago and the diagnostic didn't show anything out of the ordinary. It certainly sounds like a TPS issue. Was it replaced under recall?

 

[Bungie]

Could be clutch too.

Put it in 5th at about 40mph and whack it WFO. If the revs rise but the bike doesn't go any faster, you clutch is nearing end of life.

 

[maddad]

I know clutch is near end of life but even if I go slow up to 6500 RPM it does the same thing. So I'll pull off the TPS and have a closer look.

 

[Aasland]

I know clutch is near end of life.

I'm not aware that our wet-clutches have an expected life span? It's pretty rare for a clutch to need replacement unless it has been subjected to repeated drag launches. This may just be a red herring; my vote is also TPS.