Loomin hell

Out of curiosity and for the benefit of mankind and fellow gsers I've tried fitting year specific chips into different year motronics and you get all sorts of strange side effects :eek .

BBPower have different chips for '98-'99 and '00-'02 so that makes sense - there must be some difference internally.
 
Bugger

See title. Bugger bugger bugger bugger. I spoke too soon. I stripped the 850 at the weekend ready for engine painting so I'm back using the 1150 for commuting for the first time since I put the 'new' ECU in. Far superior bike to the 850 IMO (much quicker and torquier, smoother engine, MUCH smoother gearbox, better switchgear etc etc etc) but........





.....it's not running right. In fact (having used it yesterday and today) it seems to be getting worse again. :blast

I think it might have to go - I just can't be doing with this any more :(

monkeyboy, is yours still OK?
 
S S S S S Stutter

Gents

I also have a 2002 1150 exhibiting the same lurching around the 2750 - 3000 rpm mark. I use the bike 12 months of the year to commute 140 miles a day and she has 85k on the clock.

The sssstutter sssstarted some time ago and has got progressively worse. I ride motorway to work in the morning so no problem, but on the way home I ride one of our classic A roads.

I should be loving this journey (as I used to do!) but this lurching now causes a major A road nightmare. When cruising through the villages at about the 30-40mph mark on a steady throttle the bike constantly f**ts, lurches and coughes. The only way round is either change up (poor acceleration away or bash down multiple gears at low revs) or change down (engine over revving and very noisy) It ruins the whole run.

I have spoken to one of the chaps at work who has chopped in his 2002 1150RT for a new 1200RT just because of this same issue. Maybe that is BMW's ploy!!

My question, finally, is - Does the 2001 ECU solve the problem? Since following this thread I have purchased a 2001 ECU but I am loathed to swap it if it does not solve the problem.

Many thanks in anticipation

Regards

Dazlove
 
My results are not entirely conclusive in that the bike still isn't running as well as I know it could/should but certainly changing my ECU improved it significantly. Swapping the TPS from my other bike last night has helped (I think) but I also know that my TBs are a bit worn which makes getting good TB balance impossible and without perfectly balanced TBs there will be some surge. At least now I just have 'normal' surge and not the misfire that came with the '02 ECU.

It can't be a coincidence that your bike is a 2002 as was your mate at work's RT - the ECUs are the same so presumably suffer the same problem. The ECUs don't show a fault code of any sort on the dealer diagnostics, though, so a dealer won't diagnose the problem.

If you have a 2001 ECU already why are you loathe to swap it? It takes only 10 or 15 minutes and there's no risk involved - give it a try and post back on what you find.

What I do know for sure is that my bike is using less fuel (around 15% less) than with the original, faulty ECU and that can only be a good thing :thumb2
 
Gents

I also have a 2002 1150 exhibiting the same lurching around the 2750 - 3000 rpm mark. I use the bike 12 months of the year to commute 140 miles a day and she has 85k on the clock.

The sssstutter sssstarted some time ago and has got progressively worse. I ride motorway to work in the morning so no problem, but on the way home I ride one of our classic A roads.

I should be loving this journey (as I used to do!) but this lurching now causes a major A road nightmare. When cruising through the villages at about the 30-40mph mark on a steady throttle the bike constantly f**ts, lurches and coughes. The only way round is either change up (poor acceleration away or bash down multiple gears at low revs) or change down (engine over revving and very noisy) It ruins the whole run.

I have spoken to one of the chaps at work who has chopped in his 2002 1150RT for a new 1200RT just because of this same issue. Maybe that is BMW's ploy!!

My question, finally, is - Does the 2001 ECU solve the problem? Since following this thread I have purchased a 2001 ECU but I am loathed to swap it if it does not solve the problem.

Many thanks in anticipation

Regards

Dazlove

Try unplugging the lambda probe and see if the st st st st st stutter goes away.
 
Deja vu.........again.

Hi guys,
I've just stumbled onto this thread searching for clues to the problem with my bike........guess what, mine is a '02 as well. Seeing that I live in the land where the sun always shines I think we can discount extremes of temperature being the culprit.

It was weird reading your experiences, some sort of space time continuim thing going on here.........

Has anyone been in contact with BMW about this?

Now I've got to find a "new" ECU.

Can someone confirm again that ANY ECU from another single spark will fit.

Cheers,

Matt.
 
Matt, don't believe everything you read ;)

My problem is definitely not ECU-related - my judgement that a replacement from an '01 bike it had fixed the problem was based upon too short a test ride and in hindsight was more a case of wishful thinking than anything else. I rode for a couple of weeks with the older ECU and it was no different. I'm now back with my original ECU.

If the new ECU fixed monkeyboy's problem then that's great for him but the theory that there was a batch of suspect ECUs for 2002 is, I think, a fair way away from being proven based on my experience.

But if you want to try it, yes, any age of single-spark ECU will work.

I have another theory on the cause of my bike's problems and I will put this to the test later on today, posting back if it proves to be correct. But realistically I've had so many theories and none of them has proved correct yet so.......:nenau
 
Matt, don't believe everything you read ;)

My problem is definitely not ECU-related - my judgement that a replacement from an '01 bike it had fixed the problem was based upon too short a test ride and in hindsight was more a case of wishful thinking than anything else. I rode for a couple of weeks with the older ECU and it was no different. I'm now back with my original ECU.

If the new ECU fixed monkeyboy's problem then that's great for him but the theory that there was a batch of suspect ECUs for 2002 is, I think, a fair way away from being proven based on my experience.

But if you want to try it, yes, any age of single-spark ECU will work.

I have another theory on the cause of my bike's problems and I will put this to the test later on today, posting back if it proves to be correct. But realistically I've had so many theories and none of them has proved correct yet so.......:nenau

Oh balls - why did you have to bring this up again Sproggy mate.... you know, just a week before I put the bike in the crate for SA I THINK I caught it pissing around again. Like you, I'm now absolutely super sensitive to the slightest stutter or hesitation. It's currently half way across the atlantic so I can't check it at the moment.... but ... I'm seriously thinking of taking ANOTHER ECU with me just in case it starts up again. There is no guarentee of the date that my replacement ECU was made. Initially it ran like a dream and I just forgot about the problem entirely but just the last week, when there was absolutely NOTHING I could do about it, I suspect it may have started playing silly buggers. It was weird - Friday night it was fine, changed the oil over the weekend, Monday it definately felt a little under the weather. I'm crossing my fingers that it's just my imagination, but I'm not betting on it. In my case though, there seems pretty well nothing else it could possibly be but the motronic
 
I was hoping for your sake that it really was the ECU that fixed it for you, but it certainly hasn't for me.

You can tell for sure what year of ECU you have - the large, bold text number on the label (below the bar code) changed year on year.

1 342 935 is 1999 and early 2000
7 655 474 is 2000 (from March)
7 654 244 is 2001, the second one that I tried on my bike
7 667 285 is 2002, what our bikes were fitted with from the factory

I have tried both 2002 and 2001 ECUs with standard chips (every conceivable CCP setting including Steptoe's) and with a BBPower chip (3 different maps, the middle one of which should have been right for my spec) and no combination really improved things.

I've also tried swapping (in addition to everything else tried previously) injectors, TPS, oil temperature sensor and air temperature sensor. I haven't touched the hall sensors, but the wiring to them seems sound - the sensors remain an unknown.

The theory I mentioned earlier was that I could be down on compression on one cylinder but that's not the case - both cylinders show close to 10 bar which is healthy. But maybe there is some mechanical issue at the root of this and we've been on a wild goose chase looking at the electrics/electronics/fuelling?

I'll be contacting Steptoe on Monday to see if he can have a look at it sometime soon.

If I were you, under the circumstances, I'd try not to worry - neither of our bikes has shown any sign of unreliability so I'm sure it won't let you down on your trip - it's just a pain in the arse, particularly as it seems we're both super-sensitive to this problem now. If Steptoe can trace the problem on mine then maybe the same fix can be applied to yours when you meet up with it before your trip.

I don't think it can be the ECU at the root of the problem - what's the chance of 4 ECUs (your 2 and my 2) all having the same fault? Unless a fault elsewhere on the bike is screwing with them......?
 
If I were you, under the circumstances, I'd try not to worry - neither of our bikes has shown any sign of unreliability so I'm sure it won't let you down on your trip - it's just a pain in the arse, particularly as it seems we're both super-sensitive to this problem now. If Steptoe can trace the problem on mine then maybe the same fix can be applied to yours when you meet up with it before your trip.

I tell myself that all the time - it isn't going to stop, it's just a royal pain in the arse. I took mime to Steptoe and he was of the same opinion - you just need to work through the possibles. It isn't an obvious fault that's for sure. I have to say that changing the ECU was the ONLY thing that really made the bike feel right though - and for a good number of weeks too. I've got a 2000 R1100S in the garage that I'm just putting on the road and it looks like that has a compatible ECU so I'll whip it off before I go and take it with me. This trip is costing me so much cash I'm not going to have it s-s-s-sspoilt by a s-s-s-s-ttuer--ing bike under me:mad: It isn't beyond the realms of circumstance that we both has replaced faulty boxes with other faulty ones IMO. I certainly don't know what year mine was from and I don't have a note of the number. If the ECU of my S (whose engine runs like a dream even after 150k) goes into my GS, and the GS still pisses about then I'm flumoxed and I'm looking at something mechanical being the problem, but I cannot for the life of me think what
 
I've got a 2000 R1100S in the garage that I'm just putting on the road and it looks like that has a compatible ECU so I'll whip it off before I go and take it with me.

As far as I've been able to tell from comparing part numbers the 1100S ECU is different from other models so probably it isn't compatible. The 1100S has a different mechanical engine spec after all.

It isn't beyond the realms of circumstance that we both has replaced faulty boxes with other faulty ones IMO.

It's not impossible, but it doesn't seem hugely likely. While neither of the ECUs we bought to try were directly off bikes that were known to be good, ECU failures are rare as far as I know so the chances must be small.

I'd be interested to know how my ECU performs in a known-good bike, though - that would be a surefire way of knowing whether it's an ECU problem.

If the ECU of my S (whose engine runs like a dream even after 150k) goes into my GS, and the GS still pisses about then I'm flumoxed and I'm looking at something mechanical being the problem, but I cannot for the life of me think what

I was talking to a friend about this earlier today. If the problem is mechanical there are two possibilities - one, that the problem has been there since the bike was new (unlikely - it would have been noticed and fixed under warranty.......maybe.....unless the dealer just took it back and sold it to some other unsuspecting person.....) or two, that it's developed since. If it's developed since then it is presumably wear of one or more components. What could wear and cause poor running? We cam up with:

  • Cam(s) - wear on lobes (but it runs OK at higher revs)
  • Valves or valve seats (but my compression check was good)
  • Valve guides (either binding through bent valve stem or worn)
  • Cam chain (causing varying valve timing)
  • Pushrods or buckets (I know some versions of pushrod come apart, although the engine's reported to keep running OK, it just rattles from what I can tell. And mine doesn't rattle since I fitted the later tensioner)

Basically all top end stuff. Broken valve spring or worn rockers would be evident from visual inspection and/or routine servicing - mine are good. Who knows? As you say, clearly it's not something obvious.

Personally I've had enough of experimenting - spending far to much time and money over a 6 month period with nothing to show for it but a consistently poor-running bike. No more. My last hope is that Steptoe will be able to find the problem, but if not then the bike's going because I can't live with it any longer.
 
I tell myself that all the time - it isn't going to stop, it's just a royal pain in the arse. I took mime to Steptoe and he was of the same opinion - you just need to work through the possibles. It isn't an obvious fault that's for sure. I have to say that changing the ECU was the ONLY thing that really made the bike feel right though - and for a good number of weeks too. I've got a 2000 R1100S in the garage that I'm just putting on the road and it looks like that has a compatible ECU so I'll whip it off before I go and take it with me. This trip is costing me so much cash I'm not going to have it s-s-s-sspoilt by a s-s-s-s-ttuer--ing bike under me:mad: It isn't beyond the realms of circumstance that we both has replaced faulty boxes with other faulty ones IMO. I certainly don't know what year mine was from and I don't have a note of the number. If the ECU of my S (whose engine runs like a dream even after 150k) goes into my GS, and the GS still pisses about then I'm flumoxed and I'm looking at something mechanical being the problem, but I cannot for the life of me think what


Sorry to hear you guys are still having problems with this.

Just one further thought, if you're taking the ecu out of the 11S and think it will be compatable, why not stick the original ecu in the 11S and see how it reacts. If the fault shows up on that you know the ecu is to fault, if not something is causing the ecu to run poorly maybe?
It does sound to me now that something else is buggering up the ecu's. Can't remember if anything was mentioned before, but check the wiring harness for dodgy connectors etc. As Blackbird owners know the Injected Birds have a failing in the loom where there is a connector taped into the loom that collects moisture that corrodes and causes all sorts of issues. Anybody with unusual electrical problems is always recommended to fix the loom first and it nearly always needs doing and usually solves the problem. Might be worth having a look around, and if need be unwrapping any bits that are taped up to check them, just in case.
 
Out of interest, have either of you had the bike(s) checked on a dyno? If it’s fueling issue, a well set up power commander should fix it. I dragged my bike out of storage yesterday and got it going after a 5 month lay up. I experienced slight hesitation over 4K rpm which I tracked down to a slightly corroded FI connector. This probably wont be the issue if the entire loom has been changed but worth a look.

Keep us informed:thumb
 
Out of interest, have either of you had the bike(s) checked on a dyno? If it’s fueling issue, a well set up power commander should fix it.

No, but I had considered sticking it on a dyno to establish what the fuelling was doing. I just ran out of enthusiasm for it - there's no real indication that it's a fuelling problem (the plugs are a good colour) and I had to draw the line somewhere.

There's a guy in the US with an '02 GS with the same problem - he's 'solved' it by using a Teclusion unit but all he's done is throw loads more fuel into the engine which masks the problem. You can mask a lot of problems by throwing more fuel in. That's probably why my bike runs fine when it's cold - the mixture is richer. But adding fuel to mask the problem isn't a solution as far as I'm concerned - it doesn't fix anything. A standard (other than a Y-piece) GS shouldn't need the fuelling altered to run right.
 
Sproggy mate - don't loose hope. The soloution is out there somewhere! You can't really pass a dodgy bike on can you... karma will get you if you do that:)

Re the 11S ECU - perhaps I won't just slot it in if it isn't deemed compatible. If you want to send me your old ECU I'll take that and try it - that would surely tell me (as an experienced stutterer) whether your ECU is doing what mine was/is anyway. I'll see what occurs when I'm away and make a decision. I'll be driving through all sorts of conditions so it'll test it pretty well.

My feeling is that this problem is DEFINATELY electrical somewhere. Maybe my problem has gone away and I was just experiencing deja vu for a second...hopefully. If my problem HAS gone, and it'll get a good test soon, then I can lend you my good ECU (if you can wait till the bike gets back) and see what occurs on your bike

MB
 
You can't really pass a dodgy bike on can you... karma will get you if you do that:)

It got passed on to me.......:( It's been doing this since I bought it. How long has yours been playing up? Did it start gradually or suddenly? I'm sure you said further up the topic.

If you want to send me your old ECU I'll take that and try it - that would surely tell me (as an experienced stutterer) whether your ECU is doing what mine was/is anyway. I'll see what occurs when I'm away and make a decision. I'll be driving through all sorts of conditions so it'll test it pretty well.

I've got my original ECU fitted now but I could send you the '01 ECU if you wanted to try that? It didn't work for me, but who knows.....when do you leave? I think what we really need is to have one of our ECUs tried in a bike that's known to be good - if that starts stuttering then it's the ECU, if it doesn't, it's not - cross the ECU off the list and keep looking.
 
It got passed on to me.......:( It's been doing this since I bought it. How long has yours been playing up? Did it start gradually or suddenly? I'm sure you said further up the topic.

I bought mine with 11k on about 3 years ago - it's 70 on it now. It started gradually, usually in the winter months, mornings especially, it would start to stutter in the slow speed restrictions on constant throttle. I had some other problems at the same time that were confusing me. For a while it would not pull up hills above 80mph - it just like hit a speed limiter until you opened the throttle right up then it would lurch to 90. Intermittent again though. Then it started backfiring and missing big style for a while - cured by new HT leads - still had the stop at 80 though. Changed the lambda and that cured that fault (or maybe it didn't - but it went away at that point). Then the stuttering just got worse and worse this winter until I genuinely thought it was going to let me down. That's when I started the 'replace everything in the ignition' process. This trip was concentrating my mind on getting it fixed and i just kept on and on until we got where we are now.

I've got my original ECU fitted now but I could send you the '01 ECU if you wanted to try that? It didn't work for me, but who knows.....when do you leave? I think what we really need is to have one of our ECUs tried in a bike that's known to be good - if that starts stuttering then it's the ECU, if it doesn't, it's not - cross the ECU off the list and keep looking.

I leave on 17/3. I'll take it and try it over some serious miles/conditions if you like but I think your idea of testing it on a known good bike is the best one.... if only I had one! If you want to try my old ECU to see what occurs then gimme a shout and I'll send it over

MB
 
It started gradually, usually in the winter months, mornings especially, it would start to stutter in the slow speed restrictions on constant throttle.

Um.......battery/charging? I realised at the weekend when doing compression checks that my battery is getting pretty tired. I also had a suspicion for a while that the stuttering was worse when I had the heated grips on, but could never tell for sure - as you know it can be a bit intermittent. Could a weak battery and/or slightly ineffective alternator cause reduced voltage at the coil and therefore a weak spark? And higher revs would up the voltage and sort it? Batteries do have a harder time in cold weather.

I have a nearly-new battery in the 850 that I can try, plus I can switch alternators. Not to mention checking the voltage when the bike's running. Possibly more things to try that I can add to the few that Steptoe suggested this morning.

Have you changed your battery since your bike started playing up?
 
Sorry - forgot to mention that. It's got a brand spanking new Odysey gel battery too:nenau

Oh well, so much for that theory. Could still be a weak alternator, though. I realised this morning that when I first rode my bike with the 'new' ECU it had been connected up to an Optimate constantly for 2 months, not being ridden. Could a properly-charged battery be the reason why it seemed to run perfectly and prompted me to confirm that the ECU was the cause? I haven't used the Optimate since then because I've been using the bike almost every day.

I'll take some voltage readings tonight to put this theory to the test.
 


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