Fast idler cable not very effective

[Meeni]

Hey all,

It's been a while I posted, but I have a new problem I couldn't find the solution for in the archives.

All the things I'm not happy/sure about:
1. My bike suffers from a low/unstable idle when cold. So low that it may flame-off upon first minutes of riding if I have to do parking-speed maneuvers/wait at a redlight.
2. Both cables are slack at idle at the butterfly, however, the RHS is noticeably more lax (but both butterflies hit the set screw at the same time when releasing the throttle). Given that the 3k-vacuum is equal between the 2 sides, should I mess with this?
3. The fast idler cable has very little effect in the 'steady' position. It'll set the cold idle to around 950-1000 rpm, which is too low and suspected cause for problem 1.
4. Feeling the butterflies moving when actuating the fast-idler, I can feel the LHS move maybe 1 degree, while I can feel the RHS move, but it's almost nothing. This presumably should be the same at both sides?




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Other things I've checked and look normal

1. I have recently done the BBS idle speed adjustment (and valve clearance, TB-sync procedures, new plugs, etc). Symptoms improved markedly with this procedure but not fixed.
2. Vacuum at idle (hot) is identical left-to-right, 1.5 turns on both screws.
3. HOT idle is somewhat stable a 1200rpm. Even at 1200 rpm I have some misfiring, especially on the LHS cylinder, but nothing major, rpm would dip to 1100 rpm occasionally.
4. Vacuum at 3k rpm (hot) is identical left-to-right (didn't have to adjust throttle cables for that).
5. The fast idler in the 'hold' position will set the bike to idle around 1700 rpm cold. Cold start is OK (7-8 cranks before it goes).

[ckcarr]

Try setting these specs




This guy has a decent video for R1100 engines:

[JimMoore]

Your lower throttle cables have stretched. They now have too much slack. The fast idle lever takes up the slack, but doesn't move the butterflies. You need to re-do the throttle body synch. take almost all the slack out of the left cable, then balance it with the right cable.