Syncing Throttle bodies with GS 911 and Hamonizer

[Plasterman]

Can anyone help me with the procedure to synchronize throttle bodies on a R1200 RT using a harmonizer and GS911?

 

A step by step process of the procedure would be great help. I have already set the valves and would like to complete the process. I have questions like - When to shut off the actuators. What RPM to use when you balance, etc.

 

thanks

 

Tom

[JR356]

Lot of debate here and other BMW sites about parking the stepper motors with the GS911 or other means and if it really helps,lots of yea's and lots of nay's.

My experience with past non GS911 synch's and my recent synch using GS 911 is that it is smoother,but it could just be because it was has not been synch'd for a while.

 

Number of folks including guru JVB recommend throttle synch at 3500 rpm,there is no idle synch.

 

Cannot help you with the Harmonizer,I use a Twinmax.

 

JVB's website shows synch procedure.

Google or whatever search Jim Von Baden for the site.

 

JR356

[racer7]

Does not matter what you do with actuators- they only regulate idle speed and have no impact at higher rpm. You could use the GS-911 to shut them down if you wish, pull their electrical connectors or just forget about them- doesn't really matter because the point of doing a synch isn't about idle speed anyway- its controlled by the bikes computer and there are no idle adjuster screws.

 

DO NOT even think about touching the brass screws on the throttle bodies that look like idle adjusters- THEY'RE NOT!. If you do, you'll be replacing the TBs or sending them back to the factory for a recalibration which requires an appropriate flow bench setup. Though I suppose a good motor shop that has flow tools for cylinder head work or maybe even a specialist dive gear repair shop with a flow setup (very few dive places even know what this is- only the very best repair facilities would have one) could do it

 

Don't obsess about getting a perfect balance at all rpm from idle to redline, with or without actuators running. Focus on the rpm range of most sensitivity and your usual highway rpm.

 

Most sensitive rpm is a little below 2000 and then I like to check it at highway running rpm - something between 3500 - 4000 or so.

 

Actual adjustment is by the throttle side end at the motor ONLY. No need to touch other side unless you've got some sort of cable issue that needs fixing.

 

If your valve sets are good then synch is a no brainer and you'll learn it changes about zilch over time. The most accurate valve adjustments are done carefully with go/no go gauges which can guarantee valve set to nearest 0.001". Most folks are probably going to be 0.002"-0.003" tolerance using a set of single thickness gauges though someone who is good with a single blade and can do the "pull tension" check very well will do better than that.

 

For smooth running don't push your plugs forever. Gaps open out of spec after 25K and though the bike will run, it gets a little shaggier. Many of us use the NGK platinum equivalent of the stock NGK nickel electrode plug. Its at many auto parts places because its used in some BMW 6 cyl car motors and is a lot cheaper than the bikes original plugs which BMW uses for some unknown reason and are only available through dealers.

 

Be certain throttle cables are well seated in adjuster ferrules before you put the tupperware back or you'll get extra practice at its removal / replacement. Also don't forget to put the vacuum hose back on the clutch side TB and the little rubber plug on the other side- or your idle will be crap. Both are common errors by newbies and easy to commit if you get interrupted, etc....

[dirtrider]

Afternoon Tom

 

You can lock the steppers or not (your choice). Personally I don't but they should be close side to side at idle or you have other issues.

 

First thing-- MAKE DARN SURE you have some slack in your lower throttle cables on each side. If not get some in the cables (I usually do that at the upper cable adjuster near the twist grip on the PULL cable side. That gives you lower cable slack but doesn't mess up the side to side adjustment on the bottom.

 

If you don't have some lower cable slack before doing a TB balance you can easily screw up a good balance or make a good one worse.

 

Next--Get the engine fairly warm before checking but use some sort of fan blowing on the engine to prevent heating issues.

 

Then shut the engine down--

 

Next hook your balancing device hoses up to the TB nipples & make sure the hoses have solid leak free connections.

 

Next turn the key on & allow the computer to do it's full cycle (that will also allow the steppers to re-set). Don't just turn the key on then quickly start the engine.

 

Now start the engine & allow the idle to fully stabilize (give it a minute or so to fully stabilize the idle).

 

Now read the vacuum difference side to side & if over 10" of water (or convert 10" of h2o to what your device reads in) you have some sort of issue like a stepper malfunction problem, or valve adjustment issue, or engine mechanical issue, or tight cables, or throttle bore coking, or stepper pintle coking. In any case, stop & find your problem. You just won't get a good TB balance if the idle vacuum is off that far at idle to begin with. That probably also means you have/had a rather poor engine curb idle.

 

Now-(IF) you have GS-911 you can read the stepper position to see how close they are count wise. If close side to side you are good-to-go for TB balance. If the step count is way off then lock your steppers & see if you THEN have more than 10" of H2o difference side to side. If so then you have a problem so see the above on what to look for.

 

Next-- with the steppers locked or not locked (your choice) & the base idle cross side balance under 10" of H2o (personally I like it to be below 5" of H2o on my own bike) slowly raise the engine RPM to between 1500 & 1800 RPM's then see what your side to side balance is, if under 6" H2o (BMW spec is 6" of H2o but personally I like to have it under 2" H2o) you are good to go as is. If above 6" of H20 difference then adjust the R/H lower cable at the TB furrel & check it again.

 

If you made a cable adjustment Revv the engine a couple of times then re-check the side to side in the 1500-1800 range.

 

So now you should have the hot curb idle balance CHECKED & the off-idle 1500-1800 RPM range checked/or/set.

 

Now comes the important part for launch smoothness & just off-idle runability.

 

With the idle stable & as even as possible & with the steppers released & controlling the idle speed use the twist grip & open the throttle ever so slightly & slowly while closely watching the balance gauges. You want to see BOTH sides lift off the idle stops at EXACTLY the same time. If it goes uneven just as the throttle plates start to open find out why & correct that. (this can make a big difference in launch smoothness)

 

You are done-- so put the vacuum hose back on the L/H side, re-cap the R/H side & re-adjust the upper pull cable by the twist grip to put the grip slack where you like it.

 

[kellenbenz]

Tom,

 

I just did my RT for the first time and I admit that I was hesitant at first. After the valve adjustment, I connected the GS911 and checked all faults. Then I used the Idle Actuator Calibration on the engine menu and followed the instructions. Next I went into the Sync mode and once again followed the instructions of the GS 911. It will tell you when to start the engine and when not to do certain things. It also will not let you set anything until the engine is up to the proper temperature.

 

Very easy process and I was amazed with the quality of the results.

 

Ron

[Plasterman]

Wow, just the wealth on knowledge I was looking for. Thanks Guy's

 

Tom

 

 

[VTBeemer]

Tom,

You will be surprised how easy it is. Couple of good YouTube videos (but you have to weed through some junkers).

Also check out this site

http://www.bmwmoa.org/forum/forumdisplay.php?f=44

Good luck. Pat

[Plasterman]

One question I forgot. Do you let the bike get to operating temp before syncing or do you do it immediately after starting?

 

Tom

 

 

[Marty Hill]

Up to temp/believe DR already said that.

[racer7]

One more thing not to get hyper over. Operating temp variations make no practical difference. Just don't do it dead cold or let the bike overheat by idling too long with no airflow on it.