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View Full Version : Surging At Idle



Tacolover
04-20-2013, 11:02 PM
Bought a 06 Ulysses from a friend with only 800 documented miles on it December 2012. Box stock ran very well but hated that sound. Sent my muffler KD Fab/Drummer and returned as "The Original Drummer." Added the K&N air filter/no airbox mods. Bought the ERIK BUELL race ecm, took it to a Harley Dealer and had TPS reset. Bike ran well but started loading up on short rides. Pulled plus, front plug center electrode had a 35-40 degree angle facing away from ground electrode. Sooty running rich and wet under compression washer. EBR suggested the Champion 10R12X instead of the 10R12A's. Changed them out, bike ran well for 50-miles then now she is very cold blooded. Starts well, idles then backpops through throttle body for 1st 1/4 mile then fairly smooth after that.

However when warm/hot the bike surges at idle badly. I'm talking 1050 rpm then drops to 800 rpm then up to 1500 then back to 1050 and keeps cycling.

I have only logged 2-tanks of gas through it and fuel was not completely out so there still may be some remaining old fuel in tank. At times there are exhaust backpops on deceleration and sometimes not. Can't figure this out. This is the 1st fuel injected bike owned. I can tune/rejet a carb well but this has me stumped.

Does anybody have any suggestions?

Please and Thank you...

marten1
06-03-2014, 04:04 PM
I had same issues happen with me, no one has replied to mine either.
did you figure out the problem?

Negative
06-04-2014, 11:21 AM
Sounds like either your idle settings are off and the ECM is trying to compensate but it's falling in and out of closed loop in the process, your O2 sensor may be on the way out, or possibly an engine temp sensor issue .... Man I've been seeing these symptoms pop up more and more often here lately ...

Do you have access to ECMspy or ECMdroid and a cable to plug in the bike and look at some readouts? ...