R1150R won't sync. No vacuum on the right side. Stumped!

[maccraith]

I have a 2003 R1150R 75,000 miles on it. It was running beautifully with the AF-XIED set on 8. No surge. Lots of giddyup. The only problem was the clacking noising coming from the right throttle body. After research and diagnosis with a stethoscope, I concluded it was a worn throttle body shaft. I ordered a Dan Cata rebuild kit from BeemerBoneyard and took my time installing it. Had no problem.

Then I proceeded with the throttle body sync. I have done this a number of times before and had no trouble. I use a CarbTune Pro and it has always worked like a charm. But not this time. Regardless of what I have done, I get no reading at all from the right cylinder. Just to be sure it wasn’t the CarbTune, I switched the hoses. No problem both sides of the CarbTune read perfectly on the left cylinder. Hooked it back up normally - still no reading on the right side. Even when I goose it - no reading. Took off the right fuel injector connection; the bike stumbled just as i expected it would with no gas going to the cylinder. Reconnected and it resumed normal idle.

So I started looking for air leaks. I sprayed every joint, bolt, nut and rubber gasket first with WD-40, then alcohol and then carb cleaner. None of it made any difference in the idle speed. Then I did a minute visual inspection with a high power flashlight. Every thing looked fine. Everything seemed to operate normally with a twist of the throttle. The pulley brought the throttle back to rest on the throttle stop with a reassuring clack. (I never touched the throttle stop screw in disassembly or reassembly.) And the cable sheath was properly seated in the adjuster at both ends.

Finally, I took the throttle body off, disassembled it and reassembled it TWICE following Cata’s directions to the letter. Upon reinstalling it, the result was the same each time - no movement of the “mercury” at idle or upon acceleration. The bike runs ok with an occasional slight hesitation at roll-on and an occasional pop through the mufferless pipe ( I have been running without the muffler but with the catalytic converter for almost a year; sweet sound and no problems).

So there it is. Anybody have any idea as to how the bike could be running normally with no vacuum on the right side and no response on a manometer on the right side? I am stumped.

[sweatmark]

Something plugging the RHS throttle body bottom nipple?

[maccraith]

Something plugging the RHS throttle body bottom nipple?

Interesting thought! I will check. Thanks.

[peels]

Something plugging the RHS throttle body bottom nipple?

Interesting thought! I will check. Thanks.

Or the tube for that particular side in the sync tool? Weird.

[maccraith]

Something plugging the RHS throttle body bottom nipple?

Exactly right! There was a chunk of congealed somethingorother in the nipple - probably from the cleaning process. Thank you very much, Sweatmark.

[sweatmark]

[CycleRob]

maccraith,
When you change the TB shaft, you have to equalize the butterfly openings to the same flow/vacuum on both sides. That means BBAS (BigBrassAirScrew) passageways are soaked and sprayed clean, then each BBAS is set to something easy like 2 turns out. It is only then that you adjust the right TB's new shaft's blue painted throttle stop screw until the vacuums are equal at idle speed. THEN you can perform the normal synch procedure for idle and on throttle (~3,000) RPM's. You prolly should have replaced both TB shafts, as the similar wear on the left TB shaft/bushing will cause erratic running behaviour, most noticeable as differing idle speeds.

[maccraith]

maccraith,
When you change the TB shaft, you have to equalize the butterfly openings to the same flow/vacuum on both sides. That means BBAS (BigBrassAirScrew) passageways are soaked and sprayed clean, then each BBAS is set to something easy like 2 turns out. It is only then that you adjust the right TB's new shaft's blue painted throttle stop screw until the vacuums are equal at idle speed. THEN you can perform the normal synch procedure for idle and on throttle (~3,000) RPM's. You prolly should have replaced both TB shafts, as the similar wear on the left TB shaft/bushing will cause erratic running behaviour, most noticeable as differing idle speeds.

Once I got everything cleaned up and reinstalled, I did a normal sync. I did not touch the the throttle stop screw (which I thought was verboten unless resetting the TPS). The sync came out perfectly at idle and 3500 rpm. Do I need to go back and redo the sync starting with the throttle stop screw?

I plan to do the left side shaft as well in the near future. Thanks for your reply.

[Roger 04 rt]

Your reasoning is good since you never touched the stop screws, assuming no one else has. How many turns for each BBS? If they're close I'd leave as it is.

Btw, even if you tweak the TPS you leave the throttle stops alone. The only reason to touch them is that someone else did. And if you ever need to, don't use zero=zero, it is wrong.

[maccraith]

Your reasoning is good since you never touched the stop screws, assuming no one else has. How many turns for each BBS? If they're close I'd leave as it is.

Btw, even if you tweak the TPS you leave the throttle stops alone. The only reason to touch them is that someone else did. And if you ever need to, don't use zero=zero, it is wrong.

They are close. I started at 2 turns for both BBAS and wound up within a 1/2 of each other. I initially set the two cables at 2mm off of stop and probably wound up 3mm on left and 4 1/2 on right. Bike runs strong and smooth. The stop screws are still painted in place. I don't think they have been touched. I am going to leave all as is. Can you direct me to correct instructions for resetting the TPS? I want to be sure I know that before rebuilding the left side throttle body.

Thanks.