Check engine light

[S_Palmer]

I did a throttle body sync today, I had a little stumble off idle so I backed out the right hand screw about 1/4 turn and synced the left to it.
The stumble is gone and it runs great and is noticeably smoother.

Now the bad, when test riding I ran it up to about 6500 rpm in 3 rd gear and chopped the throttle to try to stay close to the speed limit, about a second later the yellow check engine light came on for about 5 seconds then went out. Does it every time any body got any ideas?

Any body got any ideas what could cause this? Can the right screw being 1/4 turn out cause it? I don't know if it was doing this before adjusting the throttle bodies or not. The only
other thing I did was to cap off the test hoses and leave them in place.

 

[SpeedStar]

Check your ports where you did the sync. If it is doing it only under load when you chop the throttle, you have a vacuum leak most likely.
Make sure the connection at the three locations is tight.

 

[S_Palmer]

Good call speedstar, putting the hoses back to stock keeps the light off. What I don't understand is why, all the hose and fittings were new and tight,, oh well.

 

[jajpko]

Did you re-sync after realizing there was an air leak?

 

[Firefight911]

As an additional possibility you could just be experiencing oil slosh that causes a check engine light due to the oil moving forward and the bike, momentarily, thinking it is low on oil.

 

[S_Palmer]

Did you re-sync after realizing there was an air leak?

Didn't re-sync, the leak was in the hoses I used for sync process. I never did find the source, everything was the proper size. And properly connected. I got a definate improvement in the way it runs so I left it.