32 mpg? SOLVED

[peels]

It appears this is solved, so Ill add to first post, in case anyone comes across it.

After NEVER seeing even 40mpg, THe bike returned an almost 44mpg average on my weekend trip. and alot of it I was FLYING. so im happy now.

I think it was mixture of problems, But I REALLY believe the sticky rear brake was the major culprit.

SO if you are having LOW mpg. check sticky brakes. Plugged hoses, flush them, replace if needed, clean the slides etc. My "tell" was the BURNING hot disc after only riding 8 blocks.

after brakes are ok, do ALL the maintenance. valves, TB balance, reset motronic, new plugs...all that jazz. then. add some Techron at fuel stops.

the following thread, I will leave just as it is for future reference.

SEE BELOW for original problem.

I am displeased.

Iv'e been doing some keyboard researching...but I'm only getting more displeased the more I find, so Ill try a new post.

My bike has really never gotten the miles per gallon like i see reported, not close... Normally 34-36. I had attributed to riding style, and short commutes. But...just recently got a really good service. And babied it over two tanks. first tank. 31.6. 2nd tank, 32.4. And I had REALLY hoped it would improve. Valves, TB balance, and new plugs especially.)

So, I have some thoughts that I might have done something wrong, or overlooked something....

Ill go over my concerns.

-tb balance. it runs smooth. But I wonder, could the left side have too much slack...? The fast idle lever doesn't seem to affect idle like what Iv'e seen it should when researching. could this have an adverse affect on fuel mileage? Maybe not getting much air....therefore rich? Is there a base setting for throttle slack for left side? TB's are balanced though... New to the Beemer FI but it seems simple enough...

-canister: when I pulled the tank off this last time, the stinky gas/water/dirt mixture prompted me to yank the canister. Could I have mucked something up here? IE: capped wrong hose....maybe have a vacuum leak?

- air filter. Just thought of something....otally Forgot I failed to procure the correct air filter. I was sold the wrong one, having never seen it. lol So, just blew it out really good with air compressor.. Could that affect MPG THAT much?

-could there still be bad gas? what is the best way of draining? Maybe i didnt get it all out, after noticing the backed up drain hose....?

other things I haven't messed with, but thinking of: O2 sensor, cat code plug, Ill check my tire pressure again-they are new, wheels spin freely. Also, could it be the mix of cold weather riding, AND short commute? Both tanks. Daily commute of 22 miles round trip. 18 of which are straight line highway, 60-75mph. 2 stop signs. no stop/go

is there something more sinister afoot.... Not in panic mode, or anything, because it runs fine....just looking for the best place to start here, because I feel like it should be better.

any suggestions?

I'm all ears(eyes) thanks folks!


EDIT: For reference, I am currently looking into a dragging rear brake as the cause of the poor economy.

see thread here.

viewtopic.php?f=2&t=34197

[swamper]

Mileage on these bikes has always varied between the different riders and bikes. Mine is a 04 and my son's a 02. I get between 40-44 and he gets 36-40. This is even when we ride together on long trips. I've ridden his 02 a few time and have gotten 40-44 MPG like on my 04. So my opinion is it really is how these bikes are ridden, the smoother you can be the better your mileage will be. Oh, one more thing, the magic number is 70, anything over and the mileage drops considerable.

[P_Jensen]

The only question I would ask is: at what RPM range are you riding the bike? when riding my 04 I found that it liked to be kept above the 3000-3200 rpm's, over 4000 the milage will start to go down. The boxer twins are about torque not rpm's, ridden like a supersport in the upper rpm range will effect your milage. I usally got between 44-48 mpg in mixed riding with the higher numbers being superslab at 70-75 mph, city riding should see 40-44 mpg depending on the amount of stop and go.

[riceburner]

Remember these bikes are
a) relatively heavy for their power output.
b) possibly the most un-aerodynamic object on the road (a brick has a cleaner aero-profile).
c) not designed for fuel economy in the same way that more modern bikes are (eg F800 series BMW, NC series Hondas). (FI has come on considerably in the last 15 years or so since these bike's FI systems were designed).

[AZBMWRIDER]

I get 172-179 miles to low fuel warning on my usual commute to work, 2 miles surface streets and 9 miles urban expressway, 65 mph .
When the tepmerature gets to 100 F usually late April, I switch to premium fuel, 91 octane, then I get 192-198 miles to low fuel warning .
Rural interstate highway, 75 mph, I usually stay at 80 indicated usually 77-78 actual, get 230-235 miles to low fuel warning with regular fuel and 250-255 miles to low fuel warning with premium fuel .
The bike is stock, no modifications, no windscreen, no passenger or side bags, etc ...
I do minimal maintenance to the bike, plugs and wires every five years, air filter 8-10,000 miles .
Valve clearance check / adjustment every 10,000 miles .

[peels]

excellent replies, thanks folks. the low mpg isn't accompanied by any poor performance like id expect. And Ive used nothing but 91 octane so far this year.

Like I said, not really worried... just had hoped for better. Really do think something is up with it, based on relative fuel mileage reports from you all, as well as other "R" riders. my light comes on at 130 or less. Always has. It went on at 150 the only real long trip I had. My commute is (1 way) 7 miles at 75 mph or less. i wont lug the engine under 3500, so downshift around 70 and below. With 4 miles on either side of slow city drive with 2 stop signs and 1 stop light (always hit)

I'm going to take a highway ride this weekend and see what happens. Nearest Beemer shop has new owners, going to go to their open house.
I'd really like to see 40mpg, just "because"



Curious, did the dual spark have improved economy? (mine is single)

[peels]

OK. let's put this subject on hold for a bit...

When I synched TB's. I heeded advice I read, and did not touch the left side cable. literally..... I glanced, but i didn't get near it, really.

Well, at lunch, just went out and looked. the nut is loose. so i'm gonna guess, either A: It is now out of sync. or B: I synced it to an already left side loose cable.

I am thinking the latter. that would explain the fast idle not really being "fast", if both have too much slack.

[peels]

light popped on, on the side stand. 92 miles, its off now, but its usually not long after that. somethings definitely fishy.

to do:

-Ill redo the TB sync (AGAIN) clean em out as good as I can too....

-drain the tank completely dry.

-reset the motronic again. (not sure if I did that after the maintenance I did)

[swamper]

Good your looking into finding a problem as something is off with that mileage. After you had mentioned it I went for a 250 mile ride Monday on my bike (2004) and checked my mileage at two fill ups. The first was 45.3 MPG and the second at the end of my ride was 46.2. I was actually working the throttle a little harder than usual on the mountain twisties as there wasn't any other cars or bikes on the road. It's been a long time since I really have figure out my mileage, it was based of the bikes odo which may read high like the speedo MPH? Didn't have anything load wise but had the bags on. Gotta say the Avon Storm 2 tires heat up and stick really well even in the low 60's. Good luck with finding your problem.

[swamper]

Good read here:


R1150 Motronic Reset Time: 10 Minutes

The Motronic MA 2.4 can be reset by removing Fuse 5 or disconnecting the battery. Resetting clears out fueling corrections know as Lambda Control Factors and Long Term Fuel trims. Resetting also clears out the TPS voltage range which has to be relearned by rotating the throttle fully from stop to stop with the key on, engine not running, immediately after reset. Today I stumbled upon a third function that can be cleared, an Immobilizer function--a software lock that keeps the R1150 from starting.

By stumbling on the Immobilzer function I was able to measure how long Fuse 5 (or the battery) has to be removed until the Motronic is reset.

Backing up for a minute, I've had a new HES on hand for over 6 months and finally got around to installing it. The project requires pulling the plastic, fuel tank, alternator belt, crankshaft pulley and then the HES. Everything is reinstalled in reverse order, including re-tensioning the alternator belt to 8 NM, retorqueing to spec half a dozen bolts, and in my case replacing the alternator belt tensioning mechanism due to damaging it last time I tensioned the belt.

It was time consuming enough that I decided to attach the GS-911 and test the new HES before reinstalling the fuel tank. The new HES tested fine and just as I was wrapping up the phone rang and I stopped for lunch. An hour later I went back out, installed the fuel tank, removed the flywheel locking pin and hit the starter button to check the engine before buttoning everything up. Five tries with the starter button produced the same result: DOA, not as much as a stumble.

To make things more complicated I had redressed the wire harness running from the left handle bar because its sheathing had cracked and split.

I had that sick feeling, what had I broken: was my new HES bad, had I broken a wire in the redressed harness, or was there a problem with the fuel tank reinstall. Checked the fuel line return volume, plenty of fuel. Checked the sidestand, and RID display, all normal. Fuel pump on with key on. Wiggled the wire harness. Had the GS-911 HES test glitched the Motronic? Fuse 5 pulled for half a minute. Nothing, nada.

Forty-five minutes later it hit me, the GS-911 HES test must have locked out the Motronic. It had, and there was a simple GS-911 procedure to unlock it. Touched the starter button, cranked over once or twice, it fired right up.

The Motronic has an Immobilzer function whose state is saved in memory.

After sleeping on it I realized that I had stumbled on a way to know for sure that the Motronic was reset. A way to know that the Adaptives for fueling were cleared. I went back out to the garage and put the bike into HES test mode and tried to start the bike. No go.

To figure out the time required for a full reset, I pulled Fuse 5 for 15 seconds, 30 seconds, one minute and two minutes. In each case, the bike could not be started, therefore the memory had not been reset because the Motronic still had enough charge to keep the memory alive. Finally I pulled Fuse 5 for 5 minutes, reinstalled it, hit the start button and the bike fired right up. So to reset the Motronic, at least 5 minutes--to be sure I'd leave the fuse out 10 minutes, then reinstall and relearn the TPS range.

Motronic MA 2.4 Reset Time: Remove Fuse 5 for 10 minutes. This also means if you're quick you can disconnect battery ground briefly without resetting the Motronic.

[sykospain]

Brilliant how-to, Swamper. Is it in edited format in the FAQ list ?

AL in s.e. Spain

[peels]

thanks swamper!

I feel like I've read that before, verbatim.... maybe advrider? Only I had no idea about what I was reading at the time lol Is it 10 minutes for fuse to be out, and this is the "reset" I did this once...BUT. i then had my battery out for a few days, and then did the TB sync after new batt in, knowing my own feeble mind, I am not totally convinced I did that "reset" again afterwards


Light on now, just as I pulled into work at 129 miles. when light comes fully on, that is usually 3.8 gallons used. puttin me right about 34mpg. I BABIED this bike all week.

.that, plus the "too much slack" condition of the throttles (both sides) is where I think the problem lies. As I said before, I might re-drain my gas tank too. After seeing the stuff clogged in the overflow.

MPG just low enough to bug me.

[swamper]

You do know that the bikes are set up very lean to begin with, not the best for an air-cool.

FYI: the low fuel light on our bikes usually comes on at around 180, but isn't very accurate.

[peels]

You do know that the bikes are set up very lean to begin with, not the best for an air-cool.

FYI: the low fuel light on our bikes usually comes on at around 180, but isn't very accurate.

yeah, Its my understanding that this lean-ness can be part of the "surge" issue.

160 to 180 miles until reserve sounds more like it to me, with my riding style and 90% highway commute.

[peels]

filled up this morning...

142 miles, 4.15 gallons. 34.2 a little more typical, needs to be better still.

[peels]

exact breakdown of 3 days of riding, with the weekend quick trip north.

roughly 155 miles highway. and 4 miles city. with a 5 minute stop/go situation.

-60 miles with a 15ish mph tailwind. went 70-80 6th gear 3500-4100 rpm.
-60 miles on return leg 15 headwind, speed slowed slightly, trafficky, so used 5th more. it also rained a bit, so i wasn't watching the tach as closely.

light on at 144. filled at 159, needing 4.15 gallons. 38.3 mpg. not terrible, but I really feel like it should be better.

I should also say. that tank was on 87 "corn sludge" gas. I was low and nearest station only had that.

the previous two were 91 premium.....

[swamper]

That's actually expected mileage in my book if your up at 80 mph. Like I posted anything over 70 and the mileage on most any bike type goes all to hell. I cruise most of the time right at 69-70 on the GPS and get fairly good mileage, never under 40. I'm also running a sports sheild.

[peels]

That's actually expected mileage in my book if your up at 80 mph. Like I posted anything over 70 and the mileage on most any bike type goes all to hell. I cruise most of the time right at 69-70 on the GPS and get fairly good mileage, never under 40. I'm also running a sports sheild.

noted, thanks again. I am also "sporting" a sport shield. But I did only really go that fast when with the wind... slowed down considerably on the ride home.

curious, do you use 6th @ 70? my bike (02) feels "luggy" in 6th below 3600 or so. which indirectly prompts me to go faster. My motor likes 80+. It really feels "autobahnish" LOL you heard that word here!

thanks!

[P_Jensen]

What grade of gas are you using? 89 is the min recommened 91/93 better still. Anything above 60 mph (100kph) should be in sixth ride the torque, if you run in the 80's that would help to explain some of the reduction. I found mine liked 70 - 75 in 6th 3600 - 3800 RPM best and gave the best milage. If still no joy you might want to have a dealer set and sync the throttle bodies and valves so you have a baseline for future reference.

[swamper]

I do run 65-70 in sixth and I'll admit I'm not a high rever (another word addition to our vocabulary). I actually rarely rev over 4500 RPM and usually when i do it's in the twisties, I like to really load up the drive shaft for better bike handling. Everyone rides there bike a bit different. My son will get on the 04 which I usually ride and he is lucky to get 40 MPG where as today I rode it 120 miles in the mountains again and filled up before and after and got 44.4 MPG. On the way to the station my reserve light came on at 178, pretty close to the norm. Mine has never used low octane fuel, always use 91+ as per owners manual.