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redclfco
03-23-2009, 01:31 PM
Good Morning All~

I have been running my Wee Kawasaki (250 Super Sherpa) around for two weeks now, but just got my 05' BMW R12GS uncovered and about half cleaned up, and wanted to try the re-calibrate throttle trick to see if the old gas mileage changes as result. But I can't seem to find the thread...

Can anybody verify the "procedure" to do this?

Hook ground up, then hold the throttle to full for 30 seconds, then hook up the hot wire.

Is that it, or was I supposed to stand on one foot and have good thoughts and hold my breath while doing this?

Could anyone either direct me to the thread addressing this, or see if your memory serves you better than mine?

signed-Dumb in Minnesota

deilenberger
03-23-2009, 02:26 PM
Hooking up the ground while the + wire is disconnected is no different from having no wires connected.

IF the calibration is needed (I've never seen documentation from BMW indicating it is on the R12's) - I suspect connecting BOTH battery connections, then key on, twist it three times to full throttle, dance on your right foot while tapping the top of your head with your left hand - should do it. :whistle

Motorwerk
03-23-2009, 04:48 PM
The RT manual mentions performing the procedure after a battery replacement. And I would suspect any time the battery is disconnected.

Same dance though.

ricoshay
03-23-2009, 05:32 PM
The RT manual mentions performing the procedure after a battery replacement. And I would suspect any time the battery is disconnected.

From the Service Manual - Under Battery Installation

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Connect the positive lead to the battery's positive terminal (4).

Install protective cap (3).

Connect the negative lead to the battery's negative terminal (1), making sure that the connecting cable is routed correctly.

Switch on the ignition.

Without starting the engine, fully open the throttle once or twice so that the control unit of the BMW engine management system can register the throttle-valve positions.

Switch off the ignition

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I don't believe disconnecting the battery is required to retrain the CPU to the throttle position sensor. I've done it many times without touching any wiring.

Turn on key.
Open and close throttle once or twice immediately.
Turn off key.
You're done.

Typically, though not always, the mpg display on my RT goes lower for a while and then slowly recovers to around 42 mpg.

Good

Tbdomenz
03-24-2009, 04:18 PM
This is the first I've heard about the recalibration of the TBS. Seems to make sense but would it be correct to assume this procedure is needed after a battery disconnect and reconnect? (same battery)

Motorwerk
03-24-2009, 04:56 PM
Exactly, the only reason it's mentioned is when a battery is replaced. So a disconnection of any type would call for the procedure.

This is the same procedure that is used on the oilheads (1100/1150) series as well.

Tbdomenz
03-24-2009, 05:09 PM
thanks for the info Motorwerk, after rereading the thread I see you already mentioned what I asked about:doh Moving on from there,....... If you do not perform this procedure, what consequences are likely to occur? I'm thinking the Moronic management system is "zeroing" and "recording" the idle position of the TBS. Yes? No?

Motorwerk
03-24-2009, 10:35 PM
Some have indicated rough running especially idle. I believe that's been my experience as well. Others have mentioned poor gas mileage.

It would just take longer for the throttle-body sensor to learn its range. Eventually, over time it would make this determination, this just shortens the time to learn.

Many have made this exercise part of the throttle-body sync procedure.

Tbdomenz
03-25-2009, 12:24 AM
OK then, I'll add that to my maint regimen!

Polarbear
03-25-2009, 01:16 PM
After doing this, the system starts over and the mileage is really POOR on my GSA1200(30-33mpg). It takes a few tanks of gas to resume its normal routine and better gas mpg's. I normally get 37-39mpg on a GSA and do better ONLY when riding slow, below 70 and/or below 4000 rpm's. Longer road trips usually make it better too(mpg's). Randy:thumb :usa