Choke lever is free

[mkmd555]

R1150R 2002

Few weeks ago while I was synching the throttle, I discovered that upon closing the throttle the butterflies did not close at the same time. I was able to hear two clicks instead of one. The clicks were a bit far apart.

I traced that the right butterfly closed first by using my old faithful Littman stethoscope. Once I was sure, I unscrewed the throttle adjuster and finally both clicks were almost one.

Later, I synched the throttle with a home made 3 buck manometer.

The bike ran great great.

Few days ago, early morning, I wanted to use the choke but the lever just moved without any increase in the revs.

I can see the choke cable move, ensuring that the upper part is connected to the lever.

Where should I look now?

Summer is ending and I will need the choke soon.

Thanks in advance.

M Khan

[boxermania]

Before you do anything else, check to see that the cover of the throttle cable to the TB's right and left are seated inside the adjuster......if not that is the source of the problem and you will have to readjust the the butterflies stop.

It is very unusual for a "choke" cable to break, but it can happen.

Now to the bad news, the throttle and choke cables are just above the tranny and under the airbox.....a pain to get to.....best of luck.

[CycleRob]

mkmd555, The description was not clear which one you adjusted (left/right). Obviously when you made the adjustment (to the wrong cable?) you added extra freeplay in the cable pairs to synchronize them. Then the amount the fast idle lever lifts the throttle is wasted just taking up that "new" freeplay. The fix is to adjust them both equally until there is <1mm freeplay in both cable housings at the TB cable adjusters. You can confirm simultaneous clicks many times while doing this. Also, be aware that the adjuster ferrule is NOT turning the outer cable when you turn things. That will cause a distortion that'll mess up your perfect synch when it relaxes after you've ridden the bike a while.

I'm a little concerned why there was such a synch error to start with. There is minimal length in each TB cable going to the throttle junction box (under the airbox) where the "choke" (fast idle) cable also goes. It's possible for the cable outer to pull out of it's home position when you unknowingly disturb them, like taking the fueltank off. Check for home position by holding each TB pulley (1 at a time) while you reel on some throttle. Then listen for simultaneous click stops. You'll prolly need another TB synch after seating them hard like that. You also have a freeplay adjuster on the fast idle cable nearest the lever and the throttle cable near the twistgrip. They both should be close to zero freeplay then checked at idle at both full steering stops to confirm there is no RPM increase.

I bet THEN your fast idle will go to 2,300 (after 15 seconds) like it should.

.

[mkmd555]

Cyclerob:
Your diagnosis was correct, and so was the treatment of the "choke lever is free" problem. The choke works fine now.

Here is what I did:

I adjusted the TB cable on both sides, so the butterfly stops were just touching. I used a flashlight from below.

Second step was to synch, using the manometer and turning the BBAS to achieve alignment on the manometer.
_________________________________________
A new Question:

Why does the right side of manometer go up, meaning more vacuum, WHEN you rev-it steady to 2 thousand? (This was the same observation, even before I made the changes today)

In addition to the above, if I jerk the throttle for a fraction of a second and let the throttle recoil, both sides of the manometer read the same.

aWhat is the explanation?

Your turn!

M K

[CycleRob]

You seem to have omitted the "on throttle" (2,000 RPM) synch. It is in addition to the idle synch controlled by the BBAS. The "on throttle" synch setting is accomplished by using ONLY the throttle cable with the lower water column (heavier throttle). That adjuster will go lower very slightly (screw it in) so you don't violate the minimum freeplay settings you made, as would happen IF you adjusted the other side's cable.

The differences in the water column readings after throttle changes are caused by the normal wear in the TB butterfly shaft and bushings of your 7 year old bike (just like mine). The 45mm butterflies combined with the high intake manifold vacuum creates a great deal of force. When you yank the throttle and release it, the TB shaft just settles in a slightly different spot inside the bushing, and so does the butterflies.

The homemade dyed water manometer you're using is the most accurate tool for setting the synch. It's also the most inexpensive and therefore expendable if something or somebody crushes it. Tiny vacuum differences between the 2 intake manifolds, what you are measuring with your tool, create large distances between the 2 water column levels. You can test the sensitivity of your creation by applying the slightest vacuum or pressure with your mouth and observe how so little pressure change does so much. The best test for sensitivity is one I just performed (again) in my garage that anyone can do and nobody can dispute. Holding the manometer in my left hand and one hose 2 feet (61cm) from it's end in my right hand, I twirled the hose as fast as I could. It was Rippen! It made the sound of the wind. Centrifugal force acting on the air mass inside the single twirling hose made the liquid columns separate by TWO INCHES!! (50.8mm!!). Try THAT with your $99.95 Twinmax.