Could this be possible ?? About 500 miles ago, I changed my oil from syn3 to Mobil1 20w50 for vtwins. Every since then, it seens like I have a higher cold start idle than before. After reaching operation temps, all is back to normal. maybe just my imagination, maybe not. Any thoughts.

 

Yep...you got that crappy HD sludge out of your motor so it's running much smoother...

Seriously - not related at all. Idle control & oil are not related/paired on bike so this shouldn't affect start RPM's.

 

Actually, weight/resistance is directly related to energy required to rotate mass.

I've had to drop the idle rpm on a vehicle by over 1000 RPM by changing to lightweight internals, and if you effect the resistance and friction in rotating or reciprocating mass by enough you will notice an difference.

With that said, I'm not stating that switching from SYN3 to Mobil1 would/did alter idle RPM, however it is at least a step up in oil quality.

 

Outside temp change maybe??

 

It's not the oil. It's the cool snap...Started mine the other night. Was a good 300 faster. The computer is reading the motor temperature