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Discussion Starter · #1 ·
Is there a throttle body sync procedure somewhere? I just received my official BMW repair manual CD. There isn't anything in the CD on the sync procedure. I have a few questions. I have the 2005lt. Each throttle body has an air screw. Each throttle body is connected by a linkage the opens the butterfly valves. Do you adjust the air screws at idle then the linkage at a specified higher rpm (maybe 4000rpm) or just the linkage? If I just adjust the linkage, at what rpm?

On the r1100s, you slacken the throttle cable. Adjust the brass air screws at idle (get both cylinders even and the correct idle rpm). Then, adjust the throttle cable (linkage) so that both throttle bodies are balanced at approx 4000 rpm.

I realize the 2 engines are different, but I'm still not sure what to do with the air screws since the linkage is connected to 4 throttle bodies.

thanks, Bo
 

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Unless you are experiencing rough idle do not worry about the throttle sync. Throttle sync is an indication of the relative vacuum in the manifold and is affected by valve set so it is not always accurate. If it feels smooth at idle and on the road don't attempt to fix it because it isn't broken.
 

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My Friend Pete did his , but he had to make up a gas tank with a fuel pump to do it . The LT's gas tank is in the way to get to the adjusters, so he took it off. Then had to come up with something. I got him a fuel pump & he used it & a one gallon plastic bottle for the fuel tank. The TB's are set on a flow bench before they are put on the bike. But the cylinders on the bike may not be exactly the same as each other . So a little adjustment may not hurt , one of these years I might do mine...But not this year .. :wave
 

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Discussion Starter · #4 ·
Thanks.
I Just got the bike a week ago. Rode it from Witchita falls TX to Arlington TX. It has 29k mi on it. I'm in the process of doing all the service items. I have all the bodywork off. I see some folks on this site have done a throttle body sync. It ran real good except when I was stuck In traffic in Ft. Worth. It idled high (1500/1800rpm). I know it shouldn't be that high. I'll adjust the valves, replace the air filetr and fuel filter. Then I'll check for any air leaks. If there are no leakes, throttle body sync was my next idea. Maybe not?

Bo
 

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2005 K1200LT
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There is really no reason for them to suddenly go "out of sync" so I would look else where for the cause of the high idle. If you try a sync whithout fixing the problem first you will really have a mess on your hands. Many have done the sync and all it did was smooth out the engine a bit. Most were not off that much to begin with. Use the rear most body as the master should decide to do it. Don't mess with the air screws just the butterfly linkage. You can make a decent manometer out of clear tubing and move it from TB to TB as you progress down the line. Have not done it yet on the LT but have done it before on multiple TB setups.
 
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