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Why am I getting only 25mpg?

I've read numerous posts that claim that the factory mapping restricts a lot of the bikes potential performance.

Numerous posts by people on forums going by the seat of their pants measurements, no doubt.


Thought maybe of investing in that device that lets one download tweaked mapping from the web and install it on the Motronic while backing up the factory program. Bad idea?

Who are those "tweaked maps from the web" created by.

My friend with no experience in the matter and who has a Porsche 911 is having one hell of a time setting up his mapping. Ideally, that process is best done on a dyno if you are looking for the upteenth iota of performance. If you are not, why bother with the system in the first place. My R1150 GS Adventure is running fine using the factory Motronic. And if you've seen my numbers, I get very good gas mileage for the conditions.
 
Again, I'm a novice on these matters. I've read numerous posts that claim that the factory mapping restricts a lot of the bikes potential performance, thought maybe of investing in that device that lets one download tweaked mapping from the web and install it on the Motronic while backing up the factory program. Bad idea?

It might be fun to try but I wouldn't hope for much. As I mentioned above, the mixture "cop" riding with you is the O2 sensor. If you don't remove or change that you're stuck with fueling that keeps your catalytic converter happy, 1 lb. of fuel for every 14.7 lbs. of air. That's a lean mixture that is about 10% below the mixture that produces the best power, roughly 1 lb. of fuel for every 13.2 lbs. of air. Your Motronic is always trying to run its Closed Loop program which compares the fuel it sends in to the output of the O2 sensor.

One exception is during rapid throttle movement and acceleration. We have measured 1100s, 1150s and 1200s and found that at those times the Motronic sends out injection signals that results in a good rich mixture, between 12.0 and 13.5:1, and it ignores the O2 sensor during those times.

So if you replace or augment the stock O2 sensor with a "cop" that signal something richer than 14.7:1, for example 13.8:1, you overcome the inherent leanness of a stock bike. The three devices that do that are BMW-AF-XIED, lc-1 and PC III USB w/Wideband.

There are other things you can do too, disconnect the O2 then add fuel with a booster plug or techlusion.

Lastly, on the R1100 you can change the Coding Plug from Pink to Beige and that gets the Motronic to ignore the O2 sensor although that alone doesn't necessarily richen the mixture.
 
How has your bike fared over 200k? What was the most expensive and/or complicated repair you've had to do to the bike over these miles?

I am pleased with my bike, but it has not all been a bed of roses. First, my bike is a 1993 "beta bike" (#168 off the line). BMW made a number of changes to the bikes as they produced and learned about how they were functioning in the real world.

It came with the 1st year "noisy in neutral" transmission (which, btw, was perfectly reliable for the 40k miles I put on it). I was offered, and took advantage of, the "silent recall" BMW had on the 1st year trannies, but the 2nd generation trannies had real problems. Mine would pop out of 1st under power hard enough to go right on into 2nd. So I got another free transmission, which was solid for 110k miles (about 160k miles total). At that point, it started slipping briefly in 2nd gear under power, and so I bought a refurb transmission, which now has over 60k miles on it.

The engine was always good and only gave me surging symptoms when the TBs were out of sync, usually shortly before a scheduled service, if at all. As I mentioned, it has always delivered high 30s to low 40s gas mileage. The bike has never been babied and I have been to a number of track classes with it. At about 150k miles, the front U joint on the driveshaft blew up.

In 2002, with a bit over 160k on the odo, I shipped the bike to Germany, where I keep it today at a friend's place. At 182k miles, while I was cruising down the Autobahn at about 110mph/6,000rpm, one of the pistons broke a skirt, cocked in the bore and in the process destroyed both conrods. Everything underneath the heads was pretty much trashed, but I was able to buy and have installed a 1997 R1100RT engine with 30k kms (~18k miles) on it for about $2500.

So, that engine now has almost 60k miles on it. It runs fine and smooth. And it gets high 30s to low 40s mpg.
 
Lastly, on the R1100 you can change the Coding Plug from Pink to Beige and that gets the Motronic to ignore the O2 sensor although that alone doesn't necessarily richen the mixture.

Is there a coding plug that improves performance without bypassing the 02 sensor?
 
I am pleased with my bike, but it has not all been a bed of roses. First, my bike is a 1993 "beta bike" (#168 off the line). BMW made a number of changes to the bikes as they produced and learned about how they were functioning in the real world.

It came with the 1st year "noisy in neutral" transmission (which, btw, was perfectly reliable for the 40k miles I put on it). I was offered, and took advantage of, the "silent recall" BMW had on the 1st year trannies, but the 2nd generation trannies had real problems. Mine would pop out of 1st under power hard enough to go right on into 2nd. So I got another free transmission, which was solid for 110k miles (about 160k miles total). At that point, it started slipping briefly in 2nd gear under power, and so I bought a refurb transmission, which now has over 60k miles on it.

The engine was always good and only gave me surging symptoms when the TBs were out of sync, usually shortly before a scheduled service, if at all. As I mentioned, it has always delivered high 30s to low 40s gas mileage. The bike has never been babied and I have been to a number of track classes with it. At about 150k miles, the front U joint on the driveshaft blew up.

In 2002, with a bit over 160k on the odo, I shipped the bike to Germany, where I keep it today at a friend's place. At 182k miles, while I was cruising down the Autobahn at about 110mph/6,000rpm, one of the pistons broke a skirt, cocked in the bore and in the process destroyed both conrods. Everything underneath the heads was pretty much trashed, but I was able to buy and have installed a 1997 R1100RT engine with 30k kms (~18k miles) on it for about $2500.

So, that engine now has almost 60k miles on it. It runs fine and smooth. And it gets high 30s to low 40s mpg.

Wow...that's a rich history! Did it really pay to spend that much for a new engine verses just buying another used bike?
 
Is there a coding plug that improves performance without bypassing the 02 sensor?

No. I don't think there's a coding plug that improves performance.

The closest thing to that I have heard about is, taking the long skinny intake tubes from an R or GS and putting them on an RS or RT, and then swapping the Yellow plug out with a Pink one.
Which is what you already have.
Supposed to improve low end grunt. Whatever that is.

As kind of a fun thing to do I installed a switch instead of the coding plug so I can effectively disable closed loop whenever I want.
(well almost. The Motronic seems to only read the plug at engine start.)

So, sunny, dry day, non-ethanol 91 octane, warm engine, disable closed loop - pretty much zero burbling, popping, lurching, surging, whatever.
MPG drops somewhere around 5%, no perceptible performance improvement.
Now this is coming from the guy who says he can detect a slight increase in power resulting from running the valve lash slightly tighter than stock.
I'm just saying, even when I'm being very optimistic and even possibly using my imagination, no, I don't feel anything.

Wet day - won't idle. Again, performance is the same with the throttle open, but it won't idle. Very annoying.
Kill the engine, flip the switch back to closed loop, restart. Runs fine.
Running too rich? That would be something new and different.
I don't know, I wonder if it "learns" and modifies the "open loop" map as it goes during closed loop.
If so maybe just resetting the Motronic would fix that.

By scrupulously cleaning and synchronizing and running new plugs and making sure the lash is the same on both sides, cranking the idle speed up to 1250, etc, etc... the surging is reduced to something livable, the only remnant for me is the burbling and popping on decelleration, and very occassionally it will miss or buck.
I have learned to slip the clutch a lot at low speed, and to goose the engine gratuitously.
And the remaining burble may in fact be due to the tighter lash - it seems to make it take more revs on the starter to bring it to life, it shifts the whole torque curve further toward the red end...
Which really is less than ideal for my riding style and my thin clutch plate.

So.
When I get back to wrenching on it again I'm going to set the valve lash back to factory normal, rip the silly switch out, put the coding plug back in, put some more $8 spark plugs in it, fill it up with any old damn gas I can find, and just ride it, and let the motronic do its thing.

Later when I can afford it maybe I'll get an S1000RR for when I feel the need for some performance. I'll probably still hang on the old RT though.
 
So, sunny, dry day, non-ethanol 91 octane, warm engine, disable closed loop - pretty much zero burbling, popping, lurching, surging, whatever.
MPG drops somewhere around 5%, no perceptible performance improvement.
Now this is coming from the guy who says he can detect a slight increase in power resulting from running the valve lash slightly tighter than stock.
I'm just saying, even when I'm being very optimistic and even possibly using my imagination, no, I don't feel anything.

Wet day - won't idle. Again, performance is the same with the throttle open, but it won't idle. Very annoying.
Kill the engine, flip the switch back to closed loop, restart. Runs fine.
Running too rich? That would be something new and different.
I don't know, I wonder if it "learns" and modifies the "open loop" map as it goes during closed loop.
If so maybe just resetting the Motronic would fix that.

By scrupulously cleaning and synchronizing and running new plugs and making sure the lash is the same on both sides, cranking the idle speed up to 1250, etc, etc... the surging is reduced to something livable, the only remnant for me is the burbling and popping on decelleration, and very occassionally it will miss or buck.
I have learned to slip the clutch a lot at low speed, and to goose the engine gratuitously.
And the remaining burble may in fact be due to the tighter lash - it seems to make it take more revs on the starter to bring it to life, it shifts the whole torque curve further toward the red end...
Which really is less than ideal for my riding style and my thin clutch plate.


Way over my head, I'm still at the self oil change stage. But thanks for the education!
 
Ah yes Twisted Wrist Syndrome, caused by abnormal pelvic tilt.

Conventional treatment is to excise the excess money which has accumulated in the area near the left buttock, reducing the pelvic tilt. Usually this will provide temporary relief from twisted wrist.
:blah

now that's funny
 
Wow...that's a rich history! Did it really pay to spend that much for a new engine verses just buying another used bike?

A bike with 180k miles on it has no value as a bike; only as parts. But I am not going to spend my vacation time in Europe disassembling a bike, answering eBay questions and visiting the DHL office.

$2500 will not buy an R1100RS in Germany; and it would be expensive and annoying to have a bike registered there. The Germans have higher reg fees than even California and require an inspection every other year. So, I keep my California registration current. (This also makes me immune to the speed cameras they have.)

If you look into renting a bike over there, you find that it is typically $150/day with a 200km limit. (Yes, I know that there are cheaper deals, but not that much cheaper.) In fewer than 3 weeks I would spend the cost of replacing the engine.

Now I have a bike that has carried me a further 40k miles -- that's about 6.25¢/mile additional cost for the replacement motor. It will likely continue to carry me quite a ways, further reducing the per mile cost, for the cost of service and tires. It's all set up for me with a custom seat and various other farkles. In a way, it's not worth NOT fixing it up.
 
I doubt his AFR is that steady being right in the middle of working with an Electromotive Tech/GT system on a local owner's Porsche.

As for fuel consumption calculations, they are best done from a full tank (that is a given) to a nearly empty tank. Filling the gas tank with a mere 2 gallons for example, it is easy to add an extra 0.2 of a gallon while topping up (the inconsistent part) and that alone just threw your numbers off quite a bit.

Alex, HW was one of the beta testers for the BMW-AF-XIED. Here is his full test report: http://forums.bmwmoa.org/showthread.php?56990-2004-R1150RT-Wideband-O2-Sensors&p=880407&viewfull=1#post880407.

The AFR is the value that he set into the BMW-AF-XIED. So when he indicates 14.1, for example, he had the device set for 4% Closed Loop enrichment which means 4% richer than with the stock O2 sensor. The Motronic produces richer AFRs, between 12.5 and 13.5:1 (roughly) for accelerations and throttle open more than about 50 degrees.

RB
 
I doubt his AFR is that steady being right in the middle of working with an Electromotive Tech/GT system on a local owner's Porsche.

As for fuel consumption calculations, they are best done from a full tank (that is a given) to a nearly empty tank. Filling the gas tank with a mere 2 gallons for example, it is easy to add an extra 0.2 of a gallon while topping up (the inconsistent part) and that alone just threw your numbers off quite a bit.

Before any further incorrect assumptions are made about the fuel consumption data table Roger04RT posted (data from my 1100 RT with a beta AF-XIED device he developed installed) I should clarify that my fuel tank was filled to as near the exact same level as possible _every_ time I filled it. I always do so on the center stand when I know I am heading off immediately down the highway and will consume the top of the tank before heat expands the fuel.

Also note the large percentage of fills that are around the 200 mile mark where my tank is as "nearly empty" as I normally allow it to get. I like to keep my fuel pump submerged in fuel where it belongs and was designed to run. The tanks that were less than that were filled to maintain fuel parity in our riding group of various bikes and tank sizes.

As for AFR numbers, as Roger explained these are presets on the AF-XIED device that I was beta testing. Since then I have installed an LC-1 wideband O2 sensor on the bike with data logging capabilities and I am running tests to further Roger's research on fueling solutions for our oilheads. The results so far are not unlike those in my AF-XIED report. The data plots indicate that the Motronic is very capable of quickly adapting to changes in mixture, operating temperature and all other inputs that factor into fuel control. I have plenty of data plots to prove it however currently I am still unable to satisfactorily explain the data as well as Roger can. He is mentoring me along the learning curve. What I can tell you is that it is totally possible to rid the 1100 of it's annoying tendencies due to overly lean fueling.

And most of all, I love my '00 RT again. It runs and rides like a big twin should. :dance
 
:blah

now that's funny

Not mine.
I wish I had the memory or the actual magazine handy so I could give proper credit.
I think it was a letter to the editor in Cycle Magazine back in the 70's; it went on for about a page and I was literally rolling on the floor by the time I got through it.
 
Hah!

Great line!

Yes, and HD was the original dealership, they recently added BMW. On a side note, previous to buying my R1100R I had a Vespa GTS250 that I bought from a different HD dealership that picked up Vespa as a sideline.

YOU HAVEN'T BEEN EMASCULATED TILL YOU PICK UP A RED VESPA AT A HARLEY DEALERSHIP FULL OF HARD CORE BIKERS!!!

Back to the thread....
 
Maybe I missed it (I started skimming the posts after a while) but did it ever become clear why the bike wouldn't start after the mechanic took it for the test ride?

Thanks,

Dave McDougall
 
Maybe I missed it (I started skimming the posts after a while) but did it ever become clear why the bike wouldn't start after the mechanic took it for the test ride?

Thanks,

Dave McDougall

They claimed it was a clogged fuel line right under the gas tank, but I don't believe them for the following reasons:

a. they never billed me for the time to clean the line out(mind you they nickel and dime'ed me for everything else)
b. They were supposed to have checked the fuel line during the first $1000 overhaul visit
c. The bike started up smoothly right up until they took it in the shop to run some tests.

I'm sure they forgot to reconnect something(and don't want to admit it) just like they forgot to tighten the bolts on the front right caliper that fell off mid ride home and almost got me killed.
 
And so the story ends.

Thank you all for valuable input over the summer while I sorted out the problems with my bike! As I posted earlier, the problem was created when Bergen BMW's wrench replaced my front brake master cylinder, he over tightened the grub screw on the brake lever thus keeping the calipers from fully releasing. Ironically rxcrider nailed it a while back and on my third visit to Bergen BMW for this issue I even brought a print out of his diagnosis along with the diagram he supplied detailing the grub screw adjustment...the service agent blew it off telling me that they know better than the amateurs on the forums. Since having a local wrench adjust the grub screw and check the calipers I've been through 6 full tanks of gas so far and covering mixed styles of riding and have been getting almost exactly 40mpg after each refill....much better than before but I really want to explore what's holding back the bike from getting closer to 50mpg which many riders get. I'm finally starting to love the bike and the boxer(being a lifetime Jap 4C rider) BUT I HATE THE TURN SIGNAL HORN SETUP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! I'm going to start a new thread on that one and if any of you R1100 owners have changed the controls then please let me know what you did.
 
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