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'98 1100RT Throttle synch adj question... or a few?

mtlla70

New member
Hi again,

I'm trying to synch my throttle bodies for the first time. I have given up for the evening and will resume in the morning.
I have made a manometer as per the internet (!). It seems to work, as I can get the initial idle set just fine. I am having trouble with sync under load, however. One question I have is: On the 98 RT, do I loosen and adjust only the right-side throttle cable, or both? (The 98 has a "Y" cable with one going to each throttle body, correct? Not a crossover?) Another question: I neglected to adjust the throttle freeplay screw at the grip (should be at 1mm for sync; was at about 4mm)... will that have made a difference?

Thanks in advance from this relative DIY noob who's game to try!

N
 
Correct. You have a bowden box with two cables exiting, one to each TB. This is an easier setup to work on than the earlier crossover.

You must have "some freeplay" on both throttle bodies. If you don't have freeplay it is impossible to get idle and off-idle sync done. Just to be clear - you set your idle by adjusting the air bypass screws on the two throttle bodies (the "Big Brass Screws"). Turning the BBS clockwise will reduce air and should lower the idle. Counter-clockwise should increase air and raise the idle. Make sure you remove each screw and clean the tip, which is often coated with black residue. You also could remove the hose or cap from the metering hole at the bottom of the TB and spray TB Cleaner into the BBS opening - some of it will drip out of that hole.
Off-idle sync is set using the throttle cables. Just make sure that if you tighten either of the cables, don't eliminate all of the freeplay.
 
Correct. You have a bowden box with two cables exiting, one to each TB. This is an easier setup to work on than the earlier crossover.

You must have "some freeplay" on both throttle bodies.


Great thanks! So, do I make adjustments on both sides, or just the right? And do I set free play only at handlebars or at TBs, too? Hard to find definitive answers online. :banghead

Thanks again!

N
 
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