89 R65 Idle Issue

[72803]

My 1989 R65 runs perfectly...except. When the temperatures reach into the 80s or the bike is in slow traffic and heats up, the idle climbs to about 2000 and won't drop. The bike only has about 30K on it but obviously it has spent a lot of time sitting in the garage; maybe I need to rebuild the carbs??? Any suggestions?
Alan

 

[20774]

Probably do need to look into the carbs...plus a proper carb synch will be needed. Rising RPMs once hot is a symptom of carb settings done with a cold engine. Once the engine/carbs heat up, they act differently. That's why you have to take a 15-20 minute ride before attempting a carb synch.

 

[PGlaves]

Check for an air leak where the carbs attach. If something expands when it gets hot it could cause an air leak which could cause the high idle. Likewise, if the carb body expands slightly hot, a tired throttle shaft O ring could allow an air leak and the same symptoms.