The following is a quick tutorial on how to complete a Throttle Body Sync on a R1200 series motorcycle, up to the Wethead in 2013. This is similar to the R1100/1150 series, except for the idle sync on the 1100/1150 which is different.
Here are the basic steps I used to do a TB sync at home. Notice I do not do an idle sync, because on the 1200 it is not possible. Nor is it possible to adjust the idle speed. This is all done via the stepper motors by the computer. (Edit: Now it is possible to calibrate the stepper motors using the GS-911 tool.)
CAUTION : Read the whole procedure before beginning - I can do this in a few minutes, so I do not generally use a fan to keep the engine cool. But many take a little longer, and it is recommended that a large fan is used to ensure you do not over heat the motor.
First make sure the bike is at full temperature. I like to take a minimum 10 minutes ride. I also do the TB sync AFTER adjusting the valves to ensure the best results. See the R1200 24K service link for details.
If you still have your carbon canister on you will have this hose, otherwise you will have a cap here like the other side. Put one hose from the TwinMax on here.
Here is a photo of the Twinmax hose installed.
On this TB Sync I disconnected the stepper motors. I had the power off when I did this, and made sure the connectors wouldn’t make contact. Some say this is the right way to do it as it parks the stepper motors before starting, and ensures they do not affect the TB sync off idle.
With the engine off, I adjust the TwinMax at near maximum sensitivity to make sure the needle is centered.
I then start the bike and check it at idle. It looks the same as above, except you will notice the needle swinging back and forth less than 1-0-1 across the center. This is normal, and not adjustable at home. It shouldn’t need it anyhow. If yours is off center by more than half of one number, in other words the needle is swinging back and forth with nearly a “1” as its center, you need to have a dealer check it out.
Achieving the required slack is trickier on the R1200 because you can't feel the slack. The only way is to hook up a TwinMax type device and then loosen the cables. Tighten one side until you get a reaction from the Twinmax, then back it off about one full turn. Do the same on the other side and you have both at about 1mm slack.
From there the stepper motors will make the adjustments at idle. Keeping in mind the slack you now have, adjust your throttle bodies off idle in the usual way
I then take the rpm’s up to 2K, 3K and 4K and check the TwinMax for center. If it is not, I have to adjust it.
Note: I use a throttle lock to hold it steady, otherwise it is hard to not vary the RPM a little.
Using a 10mm wrench I loosen the lock nut. I then take it up to 4K RPM and check it again. (Note: later I found that it is better to set the cable sync at about 3000-3500.)
Now I adjust the cable using the knurled nut and my fingers. In this photo you can see me adjusting it, and that it is off center. I adjust it until it is centered.
Note: Before starting the adjustment process, make sure you have at least 1mm slack in the cables, and never adjust one side so that all the slack is gone. If you remove the slack, put it back and go adjust the other side to sync.
To get the slack, tighten the cable, turning it counter clockwise, until the balance goes off canter at idle. Then loosen the cable one full turn. Repeat on the other side.
NOTE: Sometimes it is hard to get the nut snug, and keep the sync exact. To do this I snug down the nuts, then use a pair of pliers and gently turn the knurled nut (on the R1100/1150) to get the sync exact. Then finish tightening the lock nut to 4nm (or mildly snug).
A final check shows the sync dead on, at 2500-4000 RPM, and you are done.
Remove the TwinMax hoses, reinstall the rubber caps and/or hose, and go for a ride !