S4RS took running like crap.
Went on a group ride 2 weeks back and had some issues. Took it out last night and the issues were still there and got worse.
1. After riding for about 90 miles pulled up at a stop sign, waited a few seconds, went to slip out the clutch and the bike lurched and died. Weird. Started right up, slipped clutch, hiccup in intakes and it died. Started bike, slipped into second and was able to just barely get going. Once under way it ran and shifted fine.
Stopped for lunch and everything was good again.
2. Stopped for gas. After that the bike didn't seem to make much power unless pushing it very hard in a lower gear. Chalked it up to bad gas. Nobody else complained. Ran it out of fuel and filled up with new gas at the end of the ride.
Yesterday fired right up.
3. Nailed the throttle in first entering a highway from a red light. Bike seemed to bang off the redline right away without much power. Thought the clutch might be slipping and some of the previous problems.
4. On highway noticed if I was cruising at 70 in 5th around 5,000 rpm and pulled WOT quickly the engine would bog down like it was going to die. I could hear the engine struggle through the intakes. Bike ran fine if not ran hard. No strange noises or other issues. No CEL.
5. Got to where I was going and pulled up at a light to find the idle around 3,000 rpm. It finally slowed. Then crept back up. If I blipped the throttle it would hang at 3,500 for about 1 minute before very slowly coming down. < That rules out clutch issues.
Today I spoke with some tech friends and they seem to think it's the stepper motor. If so, one recommends replacing the entire throttle bodies. One says he can source the stepper motor for about $800. Another says to just delete the stepper motor altogether by having it's code removed from the ECU. One hold out said he thinks the ECU is fried and giving me problems. Ugh, I hate all this electrics.
Anyone care to add their opinions?
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