tb sync

[rkclimer]

Can anyone lead me to the location of a good tb sync procedure for a 2000 RT. Did a search and no matter how I put it in, I can not find it.

Ken

[Tom P]

Try this LINK

[DaveyMac]

Check your PMs I sent you

DaveyMac

[rkclimer]

Thanks for the reply. Will try the one you pm'd to me.

Thanks again

Ken

[DaveyMac]

That's OK, but I can't take credit for that Info, Ken H. sent it to me.

D.

[Tom P]

Check your PMs I sent you

DaveyMac

Care to share it with the rest of us?

[Ken H.]

Care to share it with the rest of us?

As the author of the mentioned document, I'll respond:

 

I have posted the TB sync procedure I wrote up here before, the last time maybe a year or so ago. Recently I've privately sent it to about 10 people who requested it, rather than posting it in the open forum because for one thing it's rather long. But also because to be truthful, it always generates some 'flaying of arms" from the group of people who are proponents of the philosophy that you should never deviate from the "BMW Way" of doing things on these bikes. Which this procedure definitely does.

 

But never-the-less, with apologies to those who have seen this before, and with no plans or intent on my part to defend or argue about whether or not this is the right/wrong or otherwise way to a TB sync on a R-bike, here it is:

__________________________________________________

 

R-Bike Throttle Body Synchronization

as told by Ken Harbeck with contributions at bmwsporttouring.com

 

Like many things on these bikes, there are differences of opinions. How to best do a Throttle Body (TB) sync being no different. Some of us feel the official BMW method is too much orientated toward getting it done within the shop book rate time. Close enough for factory work, but a more comprehensive method will bring better results. Thus I developed a procedure that while more involved, I feel will result in a smoother, more surge-free, more enjoyable ride.

 

Keep in mind also that a valve adjustment, spark plug replacement, and any other maintenance work should come first. The TB sync is the last step in a tune up.

 

And of course I have to throw a disclaimer in here that following my method is at your own risk, no warranty expressed or implied, blah, blah, blah… If you follow this carefully I think you will be happy with the results, but ultimately it’s your bike.

 

Here is the 20-step procedure. Enjoy:

 

1) Remove all the tupperware, both sides. Probably goes with out saying, but there, I just said it!

 

2) a) First we want all cables loose and for now, out of the picture. Loosen both throttle cables on each side at their adjustment point above the bell crank on the TBs. The cable has a lock nut and a threaded barrel end. Turn in the barrel clockwise, down, to loosen the cable.

 

b) Also loosen the upper throttle cable at the handlebar (push the weatherproofing boot back to access the adjustment).

 

c) Then loosen the fast-idle cable at the fast-idle lever at the left handlebar.

 

What we want is for both TBs to be on their idle stop screws with absolutely no interference from the cables. These idle stop screws are located on the inside back of the TBs just behind the air intake tubes. The bell crank rotates when the throttle cables pull and have a stop tab on them. When the TB is closed, I. e. - at idle, this stop tab rest on an idle stop screw that is held in place with a lock nut.

 

It is IMPORTANT to be aware that the LEFT idle stop screw is NEVER adjusted during a normal sync procedure. If it has been adjusted, there is a procedure to (maybe) get it back, but that procedure is not detailed here.

 

3) The ends of the cables at their adjusters at the TBs need to be able to rotate freely in their barrel retainers for the adjustments to follow to stand a chance. A small shot of lubricant may be in order here. Pull them up and out of the retainer and lube the end a bit. Make sure they are then fully seated back in.

 

It also bears mentioning that there is a guy, Marc Parnes, who makes a wonderful little tool that you permanently mount on the cable sleeves for adjusting the cables easily. http://www.marcparnes.com/. He says you only need one for the right side, but I have one on each side and I think it helps both. You will have to decide if you want to spend the $$ and wait to get them before you proceed or not.

 

4) Next remove and clean the Large Brass Screws (LBS) on the TB on each side and reinstall them at 1½ turn out from lightly but fully seated.

 

5) Next tighten the LEFT throttle cable up some to take some of the slack out. But not so far that the left TB comes off its idle stop.

 

6) You didn’t mention if you are running with the stock Cat Code Plug (CCP), none, or one of the variations that are out there. Decide now which of the Cat Code Plugs (or none) you are going to run with and do that now.

 

Personally I’d recommend starting with the stock plug in place and only try something different if at the end of the day you are still not happy with the way the bike runs. Plus it’s better on the environment. (Socially-conscious me just has to throw that in!)

 

7) Remove the hoses (that come from the charcoal canister) from the nipples on the bottom of each TB and hook up whatever device you’re using to measure sync (a water manometer I hope, but whatever) and start the bike. You did remember to put a fan out in front of the bike didn’t you? Don’t be too surprised if it runs poorly at this point, In particular off of idle.

 

8) When it is warmed up, 4-5 bars or so, adjust the RIGHT idle stop screw (not the LBS!) to get in sync at idle. At this point all we care about is idle sync. Leave the left side’s stop alone! When adjusting the various places where there are lock nuts, I find it helpful to ‘sneak up’ on the final adjustment. I.e. - tighten the lock nut snug but not tight, adjust the screw (or cable barrel in a later step), then tighten the lock nut a bit more, etc.

 

9) Now start to tighten the LEFT cable until the sync at idle is effected, then back it off 1/8 of a turn. We are trying to get to is the point where the cable just DOESN’T move the TB.

 

10) As you tighten the left cable’s adjustment lock nut, recheck that you are not pulling the left TB off if its idle stop screw. It may help at this point to shut down the bike so you can listen for the 'click' as you rotate the left TB to make sure it is returning solidly to its stop and is not ‘hanging off’ the end of the cable. If you try to do this with it running the bike will just stumble as you are only opening one side (because the right side is still loose).

 

11) Now tighten the RIGHT cable up a bit, but only to get it close. Again, so it is not pulling the right TB off its stop.

 

12) Restart the bike if you shut it down. Check your tupperware up around the pipes somewhere in the next steps to make sure nothing is glowing or melting. If it seems like there is an issue, you need more fan running!

 

13) Now, what RPM do you want to high-speed sync at? If you had a surge problem, at what RPM has it been? I think I’d choose 100 RPM or so below whatever that is. Or lacking that, use 3000 RPM. If you have any type of throttle lock on the bike like a Throttlemieser, here is where it comes in handy. If not, enlist a helper to hold the bike at a steady 3000 (or whatever you choose) RPM. While holding at a steady RPM, adjust the RIGHT cable for best sync at that RPM.

 

Some people feel this part can be done just off of idle (say 1500 RPM) to avoid the whole overheating the bike, using fans, etc., issue. Personally I like to do it higher so I am somewhere in the normal range of the cables’ travel when high-speed syncing. Then deal with any heat issues by making sure I have enough airflow happening with fans out front. Only you can decide. Or heck, try both and see which way you like better!

 

14) When the bike is dropped back to idle the idle sync should have changed very little, but it might of a bit because the right side may or may not now be back on its idle stop. If it is not on the idle stop at this point, it is because the twist of the grip is pulling BOTH cables too soon. Go back and loosen the LEFT cable ever so slightly then redo step #13. DON’T now adjust either idle stop screw or you will mess up the idle sync and have to go back to step #8.

 

I need to emphasize the above as it is a point where IMHO many people mess up. When you are adjusting off-idle sync with the cable pull, and if you go back to idle and both TBs don’t return to their idle stops, the cables are too tight. The tail will chase the dog forever as one or both of the TBs are hanging off the end of its cable at idle.

 

15) If needed you can now tweak the RIGHT LBS to get any minor idle sync difference out. It should take very little. At the end of the day each LBS should be within ¼ of a turn from each other.

 

16) As you tighten the right cable’s adjustment lock nut, recheck the high-speed sync, it should track even up through the RPMs. This can be a bit tedious as tightening the nut has a tendency to move the cable around. You can go back and forth between adjusting the high-speed sync with the right cable, and slight tweaks of the idle sync with the right LBS until you are satisfied. Or have gone crazy from trying.

 

17) By this time the ONLY reason you should touch anything on the LEFT side is if you are not happy with the idle RPM. If you want to mess with the idle RPM, then, a tiny bit at a time, while watching to keep at idle in sync, adjust first the left, then the right LBSs until you have idle RPM where you want it. I like about 1100 RPM but each to their own. Really though there is little idle RPM adjustment available on these bikes. Like most modern fuel injected engines, the engine management computer controls the idle RPM and it is what it is. Re-check the sync through the RPMs as needed. A final tweak of the RIGHT LBS should give you very even tracking.

 

18) We’re just about done! At the throttle grip tighten up the upper throttle cable. BMW’s spec says 4MM of free play in the twist, but in my opinion this is a bit of a personal preference thing. But for sure you do not want it so tight so that the idle RPM starts going up.

 

This is REALLY important because if the upper throttle cable is holding the LEFT side off its idle stop, sooner or later the Motronic will loose track of the rotation range of the Throttle Position Sensor (TPS). Also of course, from a safety perspective the idle RPM should not change as you rotate the handlebars lock to lock.

 

19) Finally tighten the left side fast idle cable at the handlebar until the idle RPM begins to change, then back it off ¼ a turn. Now when you pull the fast idle level onto its first click you should get about a 1000 RPM increase on a warm bike.

 

20) Remove your sync tool, reconnect the canister hoses, button it all back up, and go ride!

 

When you get back, have a cold beverage and marvel in the new smoothness of your bike!

[killervache]

Looked at some of the links and related articles. I'm in love with my 1100RT, but I just hit a bill for $400 for the 12,000 mile maintenance (I just bought the bike a few months ago with 6482 on it, so don't worry, I'm riding it.) One of the links said the procedure was for bikes to '98?? Are there going to be different procedures for different year 1100's??

 

Also, I'd like to have the BMW shop manual, but some people have told me the Clymer is better because it's not geared toward someone working in a shop. What is the verdict on this?? I'm mechanical, and bred on a respect for perfect tolerances, so I'm positive I'll have no problems with the work, I just figured I'll let the guys at he shop do it since I don't know the bike yet. Don't want to spend that much for someone else to do a job I can do (possibly better).

 

What should I do about a manual, that's one of my biggest concerns, primarily for things such as specs and procedures specific to the bike, and other piddly stuff that a good manual should have. I'd really like to do the valves/tuneups/TBs next time (maybe sooner if I have any problems with the guy's work at the shop, but don't forsee that, great shop).

 

Thanks

Steve

[Ken H.]

One of the links said the procedure was for bikes to '98?? Are there going to be different procedures for different year 1100's??

Depends upon what procedure you are talking about. There are various opinions on how to sync a boxer. The Throttle Body Sync procedure that I wrote and is in this thread, will work for any R11XXxx. Now that being said, as mentioned, it does vary some from the official BMW method, and others published / posted here or elsewhere. Only the user can decide which variation is the one they 'believe in' and gives them the best running bike.

 

The OTHER procedure that does change between the R1100xx series and the R1150xx series is the setting of the TPS (Throttle Position Sensor). On the R1100xx series you have what is referred to as the "Zero-zero" procedure to set the TPS's position. One the R1150xx series it is done by retraining the Motronic to the full throttle range. Neither is actually required to do a TB sync, but are often referred to as part of an overall procedure of setting up or fine-tuning a boxer motor.

What should I do about a manual,

Personal opinion, I think it's worth owning all three (Clymer, Haynes & BMW CD) as each has it's strong and weak points.

[flat_twin]

Looked at some of the links and related articles. I'm in love with my 1100RT, but I just hit a bill for $400 for the 12,000 mile maintenance (I just bought the bike a few months ago with 6482 on it, so don't worry, I'm riding it.) One of the links said the procedure was for bikes to '98?? Are there going to be different procedures for different year 1100's??

 

Also, I'd like to have the BMW shop manual, but some people have told me the Clymer is better because it's not geared toward someone working in a shop. What is the verdict on this?? I'm mechanical, and bred on a respect for perfect tolerances, so I'm positive I'll have no problems with the work, I just figured I'll let the guys at he shop do it since I don't know the bike yet. Don't want to spend that much for someone else to do a job I can do (possibly better).

 

What should I do about a manual, that's one of my biggest concerns, primarily for things such as specs and procedures specific to the bike, and other piddly stuff that a good manual should have. I'd really like to do the valves/tuneups/TBs next time (maybe sooner if I have any problems with the guy's work at the shop, but don't forsee that, great shop).

 

Thanks

Steve

 

Steve, Early oilheads have a "crossover" cable which was changed around 1998. I'm guessing that's what the "up to 98" TB sync directions are about.

Once it's in sync as Ken describes, all that's required for subsequent adjustments is a little tweak of the large brass screws for idle and right side TB cable for sync of higher rpms. I just did my spring tune up and didn't have to touch anything on the TBs. Hooked up the Twinmax and all was well. It's running very well and I suspected it would need very little if any adjustment.

[killervache]

So get a Twinmax and some manuals then.

 

Where would you recommend finding the manual from BMW?? According to my dealer, BMW no longer makes it (CD or book). Someone told me to try e-bay, but I'm not sure how hot I am on that idea.

[Boffin]

So get a Twinmax and some manuals then.

 

Where would you recommend finding the manual from BMW?? According to my dealer, BMW no longer makes it (CD or book). Someone told me to try e-bay, but I'm not sure how hot I am on that idea.

 

Try Motobins in the UK. Many US BMW owners find them cheap and reliable. It should take abot 2 weeks to get to you.

 

No affiliation etc.

 

Andy