R1100RT Idle speed very fast

[SMD]

Lately, my RT's idle has been creeping up and now is around 1400 to 1500 RPM when warm. To remedy, I've done a zero=zero , set the TPS exactly at .370 tried several higher and lower TPS settings as well. I've completley closed the LBS on both sides and opened them up to 1 1/2 turns. Idle balance is perfect as is hi speed balance.

 

All the above did not lower the idle speed one iota.

 

Any ideas on what to check next ?

 

Thanks,

Scott

[GordonB]

Have you checked your choke/fastidle lever, is the cable hung up, too tight, need adjustmnt? It should be slack when closed.

[Ken H.]

Related to the possibility of a hung fast idle cable, are both throttle bodies on there idle stops when this happens?

 

If so, a vacuum leak would be the next most likely culprit.

[T__]

Lately, my RT's idle has been creeping up and now is around 1400 to 1500 RPM when warm. To remedy, I've done a zero=zero , set the TPS exactly at .370 tried several higher and lower TPS settings as well. I've completley closed the LBS on both sides and opened them up to 1 1/2 turns. Idle balance is perfect as is hi speed balance.

 

All the above did not lower the idle speed one iota.

 

Any ideas on what to check next ?

 

Thanks,

Scott

 

Scott, have you pulled the Motronic fuse for about 3 minutes to re-set the computer? If not start there..

 

The suggestion about a vacuum leak is a good one but you would think if you had a vacuum leak that effected idle speed you wouldn’t get a perfect idle balance with both the brass idle screws at 1-1/2 turns out.. Still probably not a bad idea to use an un-lit propane torch & play that around all the TBI to manifold joints & throttle plate shafts (if the idle changes you have found an intake leak..

 

Maybe give the engine oil a good sniff to see if you have gasoline in the oil (that will effect idle speed)..

 

Have you tried turning the brass idle screws in more to see if that will lower the idle speed..

 

Remember to pull the Motronic fuse & re-set the Motronic after each TPS adjustment (especially if you have operated the engine with the TPS voltage over .400 volts)..

 

Twisty

[SMD]

Well, I've checked for vacuum leaks, double checked that both throttle plates are at the stop. Disconnected the battery but only for 30 seconds.

 

One odd thing is I completely closed both brass screws and the bike still idled. Although not very good. Sounds like a vacuum leak but where?

 

I'll try pulling the fuse and letting sit for 3 minutes.

 

Scott

[SMD]

Ohh .. I disconnected the fast idle cable just to be sure