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Discussion Starter #1
Hi i just made a sync tool not sure if it will be accurate i have posted a video .i used 20 ft of clear tubing with 2 stroke engine oil the video shows it is way off at idle at about 3000 rpm its closer .is this set up accurate enough to start adjusting or is the tool flawed in some way Thanks http://www.youtube.com/watch?v=GeUGEJi8Jc4
 

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I used one of these to sync throttles on my 2010RT. Worked very well and no problems. I used tubing with an outside diameter of 1/4". I tried tubing with an ID of 1/4" and thought it a little loose. I also used ATF fluid which worked well and was easy to see. There is no adjustment for the sync at idle. I synced at 4K and then checked to see how much difference there was at other RPM. There was some small differences but I didn't worry about it and the bike now runs MUCH better.
 

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Discussion Starter #3
Hi thanks for reply is it normal to have such a difference at idle ...in the video the left is higher which side do i adjust ....thanks
 

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You ask if your set-up is accurate enough... yes, it is probably more accurate then the popular electronic devices... such as the Twinmax I have.

"Accurate " in this case also implies sensitive and touchy. If you find that your device varies too quickly from one adjustment to another you can easily change to a different fluid...

As to the other questions... you ask if the disparity is normal... well, that is hard to say since there are so many variables, including the sensitivity of your manometer. But- that is why you built it. Yes, it is ok to use.

I recommend using the left side (clutch-side) as your base and adjust the right to match it.

There have been several detailed posts lately on this subject. Check them out.
 

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Your tool should work fine.

When you turn on the ignition, let the bike go completely through its start initialization before you hit the start button - this will let the computer check and sync the stepper positions, which control idle balance. This good practice on every start.

I do not think there is any benefit to syncing as high as 4K rpm. You are trying to eliminate the difference in throttle opening. The percentage difference is larger when the throttle is nearly closed, but off idle. 2000 rpm is enough. If you have balance here, you will have balance at 4000.

I tend to adjust from the right side, but that is just because the right side of my 1200RT is easiest to access in my garage. (I think the right side has to be used on the 1100 & 1150 engines)

Your video shows out of sync one way at idle, the other way off idle. Letting the steppers sync on start should balance the idle. If not, one cable may be too tight, not allowing the throttle to close completely. Off idle the left side is higher, which you will correct yourself.

Thanks for the video. I've been using my old mercury balancer, which works fine, but the columns tend to bounce much more than your version. Might be time for a change.
 

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I totally agree with all lkraus said.

After watching your video--- several questions

do you have stock exhaust on your bike? It sounds really good.
How many miles?

What service has been done at this point? If you have not had a recent valve adjustment then
I suggest you do that first, then the TBS. Throttle Body synch. (Valves need to be done with engine cold.)
 

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Discussion Starter #7
hI IT IS STOCK EXHAUST 35000 KM JUST GOT BIKE THIS YEAR THE DEALER SAID IT WAS MAINTAINED PROPERLY ? I WILL TRY ALL SUGGESTIONS I HAVE CHECKED THE VALVES ON ONE SIDE THEY WERE GOOD I WILL DO BOTH SIDES SOON .I DID A BRAKE FLUSH.FINAL DRIVE FLUID ...THANKS
 

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lkraus said:
Your tool should work fine.

When you turn on the ignition, let the bike go completely through its start initialization before you hit the start button - this will let the computer check and sync the stepper positions, which control idle balance. This good practice on every start.

I do not think there is any benefit to syncing as high as 4K rpm. You are trying to eliminate the difference in throttle opening. The percentage difference is larger when the throttle is nearly closed, but off idle. 2000 rpm is enough. If you have balance here, you will have balance at 4000.

I tend to adjust from the right side, but that is just because the right side of my 1200RT is easiest to access in my garage. (I think the right side has to be used on the 1100 & 1150 engines)

Your video shows out of sync one way at idle, the other way off idle. Letting the steppers sync on start should balance the idle. If not, one cable may be too tight, not allowing the throttle to close completely. Off idle the left side is higher, which you will correct yourself.

Thanks for the video. I've been using my old mercury balancer, which works fine, but the columns tend to bounce much more than your version. Might be time for a change.
I agree that there is probably not much advantage to syncing at 4k. Since I tend to ride in that RPM range, I thought it would be best to have the "sweet spot" there. I will try lower RPM next time.
 

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Attempting to do the TBS at your "sweet spot" RPM is appealing and seems like the right thing to do. I tried to do that myself for several years until Paul Glaves covered the subject in an article on TBS in the BMW Owners News.

Paul is the mechanical guru as far as many of us are concerned. His theory is that the vacuums on the 2 throttle bodies are more sensitive and it is easier to detect imbalances when the RPMs care just above idle.

At 4k the fuel/air mix is flowing at relatively high speed and trying to achieve balance there is more difficult than at the RPM just above idle. I altered my TBS to accomodate his theory and I personally think it works better there, is easier to achieve the balance I am looking for and the bike runs smoother at the higher RPM- as intended.

Not only that the TBS process at 1500 to 2000 RPM is quieter, makes less heat and fury and just works better.

Give it a try next time and see how it goes for you.

and for Vulch... checking valves on just one side was probably instructive for you with a new bike, but do not try to read much into it. Same for the dealer comments that all services were done.

I suggest you visit with the Service Adviser and have a chat, maybe buy him a cup of coffee or a soft drink. Ask him to print out the bike service history and remove the previous owner(s) names and private information. All that data is on the big BMW computer in the sky and is available if you ask nicely. This is the only way to learn what the "official" record says.

You need to let the bike get stone cold then do the valve clearance check and adjustments- on all 8 locations. 2 Intakes and 2 Exhausts on each side. Do it carefully.

Then reassemble the bike (you do not have to replace the body work) then warm up the bike and do the TBS. I always run my bike with a large floor fan blowing on the front end- just in front of the front wheel.

I'll venture that the bike will feel great and you will be proud.
 
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