rtallent wrote:Several weeks ago I went to balance my throttle bodies and found that the balance was off at idle -- way off. My only options for correcting the problem were to spend a day going to my dealer (a great dealer (Max BMW) but 250 miles of boring highway each way) and pay probably at least $100 or spend $300 to buy a GS-911 and fix the problem myself. I like my dealership and support them whenever possible, but I just don't have a day to spend doing that. Also, I like to do whatever work I can myself so I bit the bullet and bought the GS-911.
It's an expensive tool, but it works very well. In less than an hour I had recalibrated the idle actuators and then locked them so I could balance the throttle bodies at idle. That done, I was able to properly balance the throttle bodies off idle. Simple. It doesn't have much in the way of documentation, but the interface is excellent and leads you through all the steps. And I have it for the next time I need it.
Bob, just curious - what did you adjust to balance the TB's at idle? Hopefully not the green painted throttle stop screws on the TBs.. If it was done using the cable adjustments, this is also not how it should be done. Both TB's should be on the throttle stops when the throttle isn't turned.
http://www.bmwmoa.org/forum/showthread.php?t=35446
It's normal for the TB's to be out of balance at idle.. I've rarely seen mine matched. The steppers are constantly varying the balance of the two TB's when at idle to achieve the best idle quality with the lowest emissions.
The lock stepper motor function on the GS-911 is used to balance the TB's just off idle. I have found if I do a super-fanatical valve adjustment (not only making the pairs of valves feel the same, but also cylinder to cylinder feeling the same - easier done with nogo-go-nogo feelers) the TB balance has been dead nutz on above idle. I've never really had to adjust mine (36k miles at the moment.) I basically ignore the idle balance since (1) my bike has never stalled on it's own (2) I don't ride it at idle (3) from my experience - all hexheads are lumpy idlers when the engine is warm.. just a result of a lean mixture for emissions.
I bought the least expensive model, but for an additional $50 you can get one with a blue tooth interface to read and reset fault codes from a cell phone-- useful for on the road diagnostics.
All in all a very cool tool that saved me a lot of time and trouble and allowed me the satisfaction of taking care of my baby myself. Highly recommended.
The BlueTooth interface is also great for use with a Netbook. I found a USB-Bluetooth dongle for my netbook (cost was $1.00 - shipped..) that immediately spotted the GS-911 and let me not worry about dangling cable anymore. Works great. Unfortunately - Verizon doesn't seem to offer a compatible cell-phone, their proprietary OS/interface won't let you run external apps.
It is an excellent tool for anyone interested in doing their own maintenance. Stephen puts out a new beta about every month or so that adds more and more features to it. So far - no cost for updates. I'm hoping he'll enable calibrating the fuel-strips to the interface soon.. since it appears lots of us may need this somewhat frequently.
