Jump to content

Throttle adjustment on right side???


Recommended Posts

Can someone tell me when you might use the throttle adjustment hole on the right side of an RT? If there is a use how do you utilize it? Thanks


My bike is an 1100RT; 96




Link to comment


As far as i'm aware, it's intended to be used with the original crossover cable arrangment. You removed the left side tupperware, adjust the idle, using the hole in the right side fairing. Then you adjusted the cable on the left side only.

The newer junction box system, used from mid 96, requires both side tupperware to be removed. The hole in the fairing is no longer relevant, but it must be more expensive to change the molds.


HTH Daniël

Link to comment

Thanks!!! That is kinda what I thought. I always use a hydrometer when I adjust idle or sync so the plastic always comes off. I hate to admit it but I have gotten quite good at its removel.

Link to comment

interesting. i was wondering about those holes too.


can we talk about synching? i did my bike on the weekend with the ATFometer (hehe =>homemade manometer 25 ' of 1/4" filled with ATF).


Instructions have us adjust at idle using BBS then at something above idle (cracked throttle, 2k, 3k, 4k depends on author) using just the cables tension on one side. instructions made it sound easy 2 step operation. was totally not the case for me - needed many iterations.


although my throttle clearly snapping shut (and cable therefor loose) i found that by playing with the cables it impacted idle balance. by playing with the screws it impacted off idle balance. basically a lot of iterations required to get it to balance. back and forth, side to side on the cables and the BBS. i actually never got it balanced at idle (steady but out) stopped when i finally got it to rock solid balance under slow roll up and down to 3.5krpm.


i attribute my challenges to learning curve (first time) hope it will go better next time! did all the things like check for rocks and make sure cable sleeve not turning. after the fact the only thing i can think of is that tuning is sensitive to need to tighten the 10mm nut each try. i did not clean BBS or check for leaks because i could see that moving the cables caused big impact to manometer.


was pleased on test ride. crisper throttle response. no crappy noises on decel (i think was the valves which were tight). maybe i detect a low thrumming at steady 4K but not sure if i am overly sensitive. bit buzzy in the pegs and tiny mirror vibration - but i dont dont how much is normal.


questions - anybody see any obvious newby dumb mistake i am doing which made me have to iterate so much to do the tb synch? thanks.

Link to comment

"the only thing i can think of is that tuning is sensitive to need to tighten the 10mm nut each try."

Tightening the lock-nut makes a HUGE difference when I do a sync on my bike. Makes the job VERY fiddly, perfect for an anal retentive. :grin:

Link to comment

Yes a Hydrometer...vise the ATFmeter. I use colored water. I'm pretty anal about syncing and throttle response and the water seems more responsive then using ATF.


I have also found that the set screw will dramatically change the sync setting and must fiddle with it several times until I'm satisfied with the outcome. It is not a newbie problem but rather one of those things when dealing with dual throttle bodies.

Link to comment
Yes a Hydrometer...vise the ATFmeter.


Smiller is just funning with you - a hydrometer is an instrument for measuring the specific gravity of a liquid, such as the battery acid or my home-made wine (similar taste). The device you refer to is called a manometer.


And yes, this is an itterative process, though I find these days I need far fewer itterations because of refined technique.



Link to comment

I have a few 'techniques' that make TBS sync easier and more accurate (for me, at least ...YMMV)


1. Make sure the cables are well seated and throttles close completely, otherwise you can't get the idle right


2. If you are looking to achieve a very fine adjustment, then engine temperature management is important.

- don't start work until the motor is at operating temp ... 5 bars on my RT

- use a large fan running at high speed directly on the oil cooler.

- don't be afraid to turn the engine off - it takes a long time to cool down


3. After warm up, adjust the idle balance and as long as the BBS are about the same number of turns, forget about it for a while.


Now the technique ...


I found that trying to adjust the barrel, tighten the lock, twist the trottle, unlock the barrel, turn the barrel, lock the barrel ... over and over again while I was watching the manometer, was just a waste of time. My sainted mother used to say 'the hurrier I go, the behinder I get'.


I was in the middle of one of these procedures when I noticed that the cable sheath would also turn ever so slightly when I was turning the barrel ... AH HA!! That's why my PERFECT balancing act only lasts a little while ... the tension in the cable sheath eventually vibrates it back to it's neutral position and the engine vibration returns!!


To solve this requires that you use a small set of pliers and hold the cable sheath while you turn the barrel. Since this is now a two hand job, I decided to just slow the whole process down. Here's what I do now

- idle adjust

- turn off the engine (it won't cool down enough to matter)


(I don't turn the barrel or tighten the locknut unless I have a pair of pliers on the sheath to prevent it from twisting)

- decide which cable I'm going to adjust and loosen the locknut

- start the bike and do a gross adjustment to confirm whether my 'working side' is high or low ...

- do a rough balance with the locknut loose

- tighten the locknut

- sweep the RPM range to see whether I am high or low


... begin interations of

- turn off the motor

- grasp the cable sheath

- loosen the locknut

- make a MINOR adjustment of the barrel

- tighten the locknut

- start the engine and view the result as I sweep the RPM range

... do it again using smaller steps each pass.


The lock nut will ALWAYS change the balance ... just sneaking up on the balance point is the easy way to overcome this fact. When I am satisfied, I twist tie all the tuperware nuts and go for a ride then redo the idle and check the TBS.


The combination of working slower and more systematically, and paying attention to the cable sheath twist works for me. I used to do a TBS, ride a few hundred miles and feel like I needed to do the TBS again. The inability of the bike to 'hold balance' led me to velcro a Twinmax to my fuel tank and ride around a few days with a 10mm wrench in my front pocket. We all know how sensitive this adjustment is ... the locknut tightening can make a significant difference ... so can a slight twist in the cable sheath.


Link to comment

thanks Elevenfify - lots of good learning in your post. so i am not crazy after all (or let me re-phrase - so i am not the only one who found snchyning to be non-trivial after all!) i am pretty sure i was not suffering from cable sheath twist (used to cable adjustments after 20 years of pedal bike wrenching) but was feeling a bit frantic/harassed - hovering over roaring bike- burnt knuckles etc. lots of take-aways: apply slow it down philosophy. slow and easy : turn off engine, fan at oil cooler (not at cylinders ) etc. need to budget more time for the exercise, cool day is better. i will swap out the atf for water (or jack daniels or similar). tighten the lock nut. etc.

Link to comment


This topic is now archived and is closed to further replies.

  • Create New...