Bike running rough

TimR

TimR

I just bit the bullet and got my 990 serviced, including valve check. The bike seemed fine afterwards and at the weekend I headed into North Wales for a ride.

Prior to this (2 months ago), I’d had problems with reg/rec which were resolved by fitting a MOSFET unit, but I don’t think this problem is electrics-related.

After about 100 miles (and probably 200 in total since the service) the bike started to behave strangely. I noticed revs were high and hunting in neutral at a standstill – up to about 1800 rpm. Then at around 3000rpm in the first few gears, on a neutral/light throttle the bike started to hesitate and run rough. This then spread up to about 5000rpm. The next time I stopped, the revs rose in neutral to 3000rpm. I got home OK, the bike didn’t stall and when turned off, it restarted without any trouble. There are no warning lights showing.

Yesterday I took the tank off to check there were no trapped pipes or cables – all seemed OK, the MH airbox was properly seated/secured and the rubber boots looked OK. Of course, when I put it back together and took it for a quick test ride, it didn’t show the problems. I guess it needs to be ridden for a longer time/distance to show the problem again.

I phoned the bike place that serviced it and they’ve said to bring it back in to have a look, which I am planning to do later this week. The mechanic said he thought it sounded throttle body related.

I have searched but can’t find anything to point me in a particular direction. Anyone experienced these symptoms?
TimR

TimR

The hesitating and the rising idle (to 3ktpm) i've had as well, on my bike it was the TPS... mine was broken so I replaced it and set it to the correct values and the problem was solved.