Join Date: Jun 2008
Location: Finksburg, Maryland
Mentioned: 0 Post(s)
Glitch today during warm up, motor revving past 5k rpm on it's own
When I started my bike tonight, the motor revved up much higher than normal. I gave a tad of throttle thinking the cable was stuck and it revved higher still. I looked around and found that the silver cam lobe on the right side above the FI (sub throttle servo perhaps?) was causing the bike to rev. The bike was also missing a bit. I restarted the bike several times, and tried to close the throttle by hand, but the servo was fighting me and twitching like mad when I pushed against it. I turned the bike off, and pushed the throttle closed, but when restarted it immediately revved past 5k again. I finally forced the servo back to the normal position with the motor running and very hot. I was rewarded with an error light that went away only after turning the key off and back on. I was a bit worried about this as I was getting ready to take my daughter for a quick ride. A servo suddenly taking the engine up past 5k rpm on it's own is not a good thing. It ran correctly for the rest of the ride.
I've got the service manual installed on my other PC, I'll have a look in a bit and figure out the correct technical terms.
Only mod done to the bike is the vacuum T, and it's still in place and secure. It almost seems like a position sensor was stuck or malfunctioning for a while. It's crazy that there's a servo that can automatically take the motor up WAY past it's warm up setting, the servo had plenty more room to turn and could have taken the motor up even higher. Engineers, lol.