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What Happens?

Murfee

Bon Vivant
I have a 2002 R1150RS that I absolutely love. I have a question regarding the battery and I can't find an answer through the Search tool. My manual says that if the battery is disconnected, the bike will undergo a memory loss and not function correctly. Really? Does it have to be reset or will it self-correct? Thanks for your thoughts. - Murfee:)
 
I have a 2002 R1150RS that I absolutely love. I have a question regarding the battery and I can't find an answer through the Search tool. My manual says that if the battery is disconnected, the bike will undergo a memory loss and not function correctly. Really? Does it have to be reset or will it self-correct? Thanks for your thoughts. - Murfee:)

The Motronic will lose it's memory I think. To reset, once the battery is reconnected, turn the ignition key to ON, but do NOT start the bike. With the key on, rotate the throttle to full open and close a couple of times. Turn the key off, and voila the throttle sensor is reset. Now you can start the bike....
 
The Motronic will lose it's memory I think. To reset, once the battery is reconnected, turn the ignition key to ON, but do NOT start the bike. With the key on, rotate the throttle to full open and close a couple of times. Turn the key off, and voila the throttle sensor is reset. Now you can start the bike....

Really? I replaced the battery on my S a couple of years ago and didn't experience any issues.

Edit: After doing a little googling it appears SeabeckS may be onto something here.
 
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Well, since I just replaced the battery in the S last weekend....

Though I wasn't entirely sure this advice would be relevant for an RS, they're such strange beasts.:D
 
Googling? Try looking in BMW service literature.

That's not nearly as much fun as sifting through mountains of misinformation, opinions, and old wive's tales before finally happening upon that kernel of wisdom which leads to a bona fide answer. :D

Here's a question: When I replaced my battery I didn't do the open-the-throttle-a-couple-of-times procedure. Bike seems to run fine and dandy (and much better than those schoolbus yellow/lead pencil grey models). Should I disconnect the battery and run through this procedure or might I be delving into "if it ain't broke - fix it 'til it is" territory?
 
TPS learning applies to Motronic 2.4 but not to 2.2. Generally that translates into R1100 no. R1150 yes. I forget, but think the 1100S is a 2.4.
 
Thanks, people. My manual made it sound drastic and I couldn't believe a touring company like BMW would inflict that on a rider. They should, however, put the re-set procedure in the manual. Thanks, again.:clap
 
Thanks, people. My manual made it sound drastic and I couldn't believe a touring company like BMW would inflict that on a rider. They should, however, put the re-set procedure in the manual. Thanks, again.:clap

You are most welcome...the manual for my S only mentions this procedure in the section dealing with battery replacement. But I think Mr. Glaves is correct...he usually is! :bow

Cheers!
 
1200s too;

According to my dealer the '07 1200s are too, the same procedure. My fuel mileage suffered greatly, after battery swap and eventually came back. I did the throttle twist agenda, per my dealer instructions. I was on cross country trip and called them from the road, as it was so bad! Seems my bike also went into some kind of HP GAIN mode too, because it had power I never felt before(A LOT MORE). Mine took a while to stop this after battery change...This too, may apply to 1150s, not sure. Randy
 
you lose the time in the clock. You do the TPS reset or not, it will run either way. In fact I could tell no difference. Not in mileage or power. Some may, but mine did not. Probably because it is the faster and superior blue color.

Rod
 
I have a 2002 R1150RS that I absolutely love. I have a question regarding the battery and I can't find an answer through the Search tool. My manual says that if the battery is disconnected, the bike will undergo a memory loss and not function correctly. Really? Does it have to be reset or will it self-correct? Thanks for your thoughts. - Murfee:)

On the R1150 series of motorcycles (and the R1200s and the R1100S with Motronic MA 2.4), my tests and the service literature are very specific. When you disconnect the battery (or remove Fuse 5 which powers the Motronic) you will lose "Adaptation Values" (see quote from Service Manual below) and the TPS "registration". You lose them because they are stored in memory powered by the 12V main battery.

Losing these values does no harm, and causes no permanent effect (and can be helpful at times). The TPS is reregistered (whatever "reregistered" means) after a battery disconnection by turning the Key to ON but not starting the motorcycle and turning the throttle twice from fully open to fully closed (fast idle lever fully down); then turning the Key OFF, then starting as normal.

The Adaptation Values are relearned after the motorcycle is fully warmed up and you ride it for a while (1/4 tank of gas gets a lot of the relearning done but not all).

These Adaptation Values are learned when the Motronic compares two calculations that it makes: 1) how much fuel the O2 sensor says is needed (Closed Loop) to hit an AFR of 14.7:1 and 2) how much fuel is needed when it uses fuel table plus air sensor plus barometer plus battery voltgage (Open Loop). The Adaptation Values are applied to Open Loop fueling: Cold Start, Acceleration, Deceleration, throttle open more than 50/60 degrees.

VERY SIMPLY, say you are riding steadily at 8 degrees throttle and 3000 rpm, if the Closed Loop fuel pulse to hit 14.7:1 is 2.575 milliseconds but the Open Loop calculation says it should take 2.500 milliseconds, the Motronic "learns" that it takes 3% more fuel to hit 14.7:1 than the fuel tables and sensors say. Because the O2 sensor is very accurate, the Motronic remembers an Adaptation Value and saves it in the temporary memory. The next time it has to calculate fuel without the help of the O2 sensor, it applies that 3% learned number.

That process also happens at many RPMs and TPS levels, including IDLE. Therefore after you ride for a while, after a battery disconnect, the starting and idle get better.

So disconnect without fear, just reregister the TPS and ride for a while.
RB

PS. Although I haven't measured it myself, the Motronic MA 2.2 on the R1100 surely stores some Adaptation Values. It's pretty hard to make an FI computer work without at least some learning. More later after I get an LC-1 on an R1100. The Bosch engineers designed the software to do this 15 years before any Oilhead was produced.

Quote from BMW Service Manual

Note:
Disconnecting the battery means that the entries in
the fault memory of the Motronic MA2.4 control unit
are deleted and the adaptation values are reset.
This can temporarily impair the operating characteristics
when the engine is restarted.
 
TPS learning applies to Motronic 2.4 but not to 2.2. Generally that translates into R1100 no. R1150 yes. I forget, but think the 1100S is a 2.4.

Paul is correct. The R1100S has a Motronic MA 2.4 and requires the same procedures for TPS reregistration as all 1150s.

Thanks, people. My manual made it sound drastic and I couldn't believe a touring company like BMW would inflict that on a rider. They should, however, put the re-set procedure in the manual. Thanks, again.:clap

From the Manual
Disconnecting the battery means that the entries in
the fault memory of the Motronic MA2.4 control unit
are deleted and the adaptation values are reset.
This can temporarily impair the operating characteristics
when the engine is restarted.
? Disconnect the negative terminal of the battery.
? Pull the battery to the left to remove.
? Disconnect the positive terminal of the battery.
? If necessary, top up the acid level to
the ?MAX? mark with distilled water.
? Clean and grease the battery terminals.
? Installation is the reverse of the removal procedure.
? Switch on the ignition.
? Without starting the engine, fully open the throttle
once or twice so that the Motronic control unit
can register the throttle-valve positions.


According to my dealer the '07 1200s are too, the same procedure. My fuel mileage suffered greatly, after battery swap and eventually came back. I did the throttle twist agenda, per my dealer instructions. I was on cross country trip and called them from the road, as it was so bad! Seems my bike also went into some kind of HP GAIN mode too, because it had power I never felt before(A LOT MORE). Mine took a while to stop this after battery change...This too, may apply to 1150s, not sure. Randy

The R1200s require the TPS reregistration also. I noticed on another R1200 that after reset it ran with a rich mixture until the BMS-K relearned the Adaptation Values and leaned it back out to stock. (And there was more power while temporarily richer, think about richening your mixture if you want that power back.)

you lose the time in the clock. You do the TPS reset or not, it will run either way. In fact I could tell no difference. Not in mileage or power. Some may, but mine did not. Probably because it is the faster and superior blue color.

Rod

You're right on both points. You do lose the clock and it has to be reset. I have tried many experiments to fool my R1150RT into mis-learning the TPS registration. You can fool it temporarily but as soon as it sees the correct Closed value and the correct WOT value, it learns it. Doing the TPS relearn sequence just gets it there faster. I can contrive situations where not reregistering it makes it run badly after starting but it takes a lot of work to fool it and then it eventually figures you out the instant you give it the right value! Smart devil.
 
I disconnected the battery on my R1200ST last year, did not do the re set when I reconnected it, and the bike runs fine. :scratch
 
I disconnected the battery on my R1200ST last year, did not do the re set when I reconnected it, and the bike runs fine. :scratch

When reset, a default low voltage (for Closed throttle) and a default high voltage (for WOT) are already in the BMS-K (the software programmers put them there). The closer those default values are to your bike's actual, the less you would notice it, and they should be close.

More importantly though it appears from careful measurements that I've made of the Motronic MA 2.4 (and I suspect 2.2) that it keeps track of the lowest voltage that it sees coming from the TPS. It calls that lowest voltage closed throttle. It appears to do the same thing for WOT, which is less important.

Again from my testing, the importance of knowing the TPS voltage is so that the Motronic or BMSK can accurately assess idle (0.32 degrees on the Motronic), fast idle (>1.28 degrees) and Overrun Fuel Cutoff (RPM greater than 1800 and TPS below 2 degrees). We're talking about very small numbers and very small voltages and the Motronic or BMS-K wants to know accurately when it should be in which mode.

The moral of the story is if you do nothing, it will probably be fine but if you do the TPS reregistration procedure the Motronic or in your case the BMS-K gets to the right answers faster.
 
Thanks for that, Roger. I pulled the battery right after I purchased the bike, to look for a date stamp, and I was unaware at the time, of the re set procedure.
 
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