Reply With QuoteI had just installed bar end mirrors and thought that might have been part of the cause, but I removed the right side one and it didn't make any difference. FYI the snorkel was removed by the previous owner...
03 xb9s here... So, it seems to have developed a new issue and I'm not sure what is causing it. All I did recently was adjust the idle up to 1150. Seemed to be ok, but on a recent ride after getting good and hot, the idle wouldn't fall below 2500. Also, the throttle returns to its stop pretty easily when released, but the engine rpm's don't slow down immediately, they kind of slowly slow down on their own. No coaxing of the throttle handle helps.
WTH? Any ideas? Can't see anything binding. Pulled the air cover and lifted up the base. Turned the handle bars from side to side and doesn't affect idle. I don't get it.
I had just installed bar end mirrors and thought that might have been part of the cause, but I removed the right side one and it didn't make any difference. FYI the snorkel was removed by the previous owner...
I'd start by pulling the airbox off and make sure there's nothing catching at the throttle.
Edit: oops. Missed where you said you did that
What was your idle set at before you adjusted it? If it's nothing physically binding then it's most likely electronic. The computer is a good place to start. Could be a sensor.
I read where a TPS reset might be in order, but then I also read that lowering the idle would help. I set the idle to where the service manual spec'd and I was also having a problem with engine knocking due to low oil pressure from low idle speed. It was set a 950.
High idle and slow idle return sounds to me like a vacuum leak.
^
Intake leak maybe I had the same problem.
High idle and slow idle return sounds to me like a vacuum leak.
FYI....At 950 RPM idle speed, the light MIGHT flicker after a hard, extended run (Hiway, etc.), but it shouldn't knock or tap. Make sure you're not running some piss-water 5-30 or something in the engine. 20/50 in temps over 50 degrees, (f) ,10/30 in temps below 50 degrees (f), and it will be fine. :)
try turning your idle back down just a little, see if that helps,try 950 or even 1000 rpms
Step 1) Do a TPS reset. Adjust to instructions...idle might be high or low initially. Warm up the bike til there is no cold start corrections usually 180℃. Then adjust your idle between 950-1050 RPMs. Usually a hanging idle is due to improper adjustment of idle during a TPS reset.
Step 2) If the problem is still there, check the intake seals. Manual says use a propane torch and let the gas flow around the intake flanges. Listen for a rise in idle or like mine, it lowered the idle. I used carb cleaner as the propane didn't work for me.
Step 3) Buells don't produce much oil pressure at low rpm idle, that is why good 20w50 oil is important, also IIRC there was an update to the oil pump after 03 (still bottom mounted) but better than 03 oil pump. Also the oil pump drive gear should be updated to a bronze one. The steel gears wear and can cause ugly problems, but likely not making good contact with the oil pump and causing lower pressure than normal.
Mobil 1 20w50 for V Twins is what I'm running. Just put it in a couple hundred miles ago.
Many thanks for the inputs. I was meaning to do an inspection of the oil pump drive gear but got sidetracked. Since its up on the table right now and I'm on call so I can't really go far, I might as well spend a Friday night working on it.
I'll check the oil pump first, then get a PC out in the shop to do the TPS reset. If I'm still having trouble after that I'll check for intake leakage.
I also want to go over the airbox mod that the PO did and make sure it was done correctly. If anyone has the link to the airbox mod bookmarked please post it. For some reason I have the worst luck in searching on the site...
Thanks again all, I'll post up some pics Friday night.
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