This morning on my way to work, rolling on the highway about 65mph when the engine light comes on and bike starts slowing down. bike does not die, but is idling, no response to twist of throttle. I pull over, turn the ignition off, turn back on, bike starts and runs fine the remaining 30 miles.

This is an '09 UC.

I tried a search but found no reports of this, but search is not the greatest.

Has anyone heard of this before? Don't want to get stranded.

 

Went into limp mode. Do a search there is a lot of info on this subject.
Mine done it too.

 

Had this problem on my 08 SG. It's the Throttle Control Actuator (TCA) plug in on the throttle body. It's a systemic problem. When you get home get some dielectric grease and a good contact cleaner, disconnect the TCA plug (if you're looking at your air cleaner it is behind the left side of the air cleaner, it's a decent sized black plug that connects to the throttle body) spray contact cleaner generously on the male and female receptacles, allow to dry, then spray it again and use a pipe cleaner or something small like that to get in there and dislodge any of the little "fouling hairs" that accumulated and caused the problem. Once the male and female receptacles dry again apply a good coat of dielectric grease on the male pins and plug it back in. The problem is that moisture gets in there and causes the pins to foul, producing these little fine hair like pieces that send your bike into limp mode. Others will tell you that you need to replace the entire TCA and throttle body, but I'm all for trying the cheap fix first. Worked for mine and I rode it from NC to Myrtle and back the day after it happened, then from NC to DC over Memorial Day Weekend and haven't had any issues. Once you're done make sure you reset the codes too.

 

Mine has done it twice usually right after a pit stop. Mine had to sit about 15 minutes before coming back to life. Dealer checked under warranty and indicated connector to throttle body was the problem. If you look up info on "limp mode" it is a system that drops throttle to approx 2000 rpm or less and only usable to get to a safe stop when ECM detects voltage issues on TBW circuit. Its a safety system to prevent uncontrolled throttle but is a pain in the butt when it activates. It usually also registers some TBW codes in the ECM. I'm not convinced dealer fixed the issue but it has not done it again in the last 9 months since service.

Post above indicates its caused by moisture which may be partly true but I think a big contributor is vibration of the motor chaffing the connector pins. The grease helps both issues.

 

Thanks guys for the input, I will try cleaning the connector when I get home.

 

Any updates?

 

Cleaned the connectors and added di grease last night, went for short ride last night and rode to work this morning with no issues!!!

Thanks for the help!

 

did it throw codes

 

Everything I've read...there doesn't seem to be a true "fix", yea you might get it working again..but..

Mine quite about 500yds from home..turned it off and on again and worked fine after I pulled it in the garage. Next day I fired it up and it made a horrid noise behind the air filter. Check engine light was on and wouldn't go off.

Honestly a bit nervous but rode it to the dealer through heavy traffic about 6-8 miles away. The service manager listened to the noise and immediately went to his top tech and said... "hey come check this **** out!"...never a good thing when the service manager say's that. So it appears my throttle actuator is bad..

Makes me nervous that I'm going to be pulling through and intersection or I'll be in a situation where I need to get out of the way and have no throttle. Seems this is an issue that won't go away for a lot of folks.

 

Everyone should do this as preventative maintaince, the throttle body connector as well as the ecm connector under the seat