Loomin hell

[sproggy]

Swapped the relays around yesterday morning before riding to work - no change.

In the evening I checked voltage at the battery with engine off, engine idling with and without heated grips on and also at 4k rpm. It all seems good, although the fact that there's an appropriate voltage present when the alternator's spinning doesn't necessarily mean there's sufficient current flowing. I can swap alternators at the weekend to test this further, but I don't think the charging system is at fault - it's done a couple of months of daily commutes without seeing the Optimate and it wouldn't have coped with that in this weather if the battery wasn't being charged properly.

I also swapped the battery to the new gel one from the 850.

Rode to work this morning - still running badly - at least as bad as before if not more so, but then it does vary.

New FPR arrived today so that's another job for the weekend - if that and the alternator don't help then last resort is to shell out for a hall sensor. I dream of the day I'll be able to just enjoy riding the bike, not spend hours every week working on it.....

 

[monkeyboy]

New FPR arrived today so that's another job for the weekend - if that and the alternator don't help then last resort is to shell out for a hall sensor. I dream of the day I'll be able to just enjoy riding the bike, not spend hours every week working on it.....

I've got a spare Halls sensor if you can wait till I return. They ARE the same as an R1100S if you need one BTW. Do we know if anyone else has found GS Navana after changing the ECU?

 

[sproggy]

I've got a spare Halls sensor if you can wait till I return. They ARE the same as an R1100S if you need one BTW.

Thanks, but my patience is running out and I don't think I can wait! I'm so desperate I even considered part-exchanging it for a 1200.......for about a quarter of a second (been there, done that, regretted it).

Do we know if anyone else has found GS Navana after changing the ECU?

They've all gone quiet haven't they? I reckon they're waiting for us to find the solution

I've just had the idea of borrowing an oscilloscope from work to connect up to the injectors (one at a time) to test the pulse reaching them. And also to connect up to the low tension side of the coil to check the pulse there. Both should be regular and even at a constant idle. Or as constant an idle as is possible on my bike.

Doing this would, I reckon, determine once and for all whether it was an electrical problem. If the pulses are regular then it's either fuel flow/pressure or something mechanical. Probably. Maybe.

 

[monkeyboy]

I've just had the idea of borrowing an oscilloscope from work to connect up to the injectors (one at a time) to test the pulse reaching them. And also to connect up to the low tension side of the coil to check the pulse there. Both should be regular and even at a constant idle. Or as constant an idle as is possible on my bike.

Doing this would, I reckon, determine once and for all whether it was an electrical problem. If the pulses are regular then it's either fuel flow/pressure or something mechanical. Probably. Maybe.

Yep, I possibly reckon doing that would maybe probably definately take up some time and would give your eyes and brain a workout then lead you gently though positively along a dark and winding path all the way back to square one

Feck knows mate - I think the Molotov is the only solution. I'm thinking of having hypnotheropy before I go to convince me all is well and is running perfectly. That's probably a better and cheaper solution than trying to hunt and kill the little German gremlin that's living in a dark recess somewhere in my GS

 

[sproggy]

Yep, I possibly reckon doing that would maybe probably definately take up some time and would give your eyes and brain a workout then lead you gently though positively along a dark and winding path all the way back to square one

I've decided not to bother - I talked to a guy at work who tried to use the same oscilloscope to diagnose a problem with his Lancia. Couldn't get a clean signal on the injectors - not enough to figure out whether or not there was a problem. In the end it turned out there wasn't, but if he'd believed the readings he'd have thought there was.

Feck knows mate - I think the Molotov is the only solution. I'm thinking of having hypnotheropy before I go to convince me all is well and is running perfectly. That's probably a better and cheaper solution than trying to hunt and kill the little German gremlin that's living in a dark recess somewhere in my GS

I'm half way to replacing the FPR - had to give up last night as I have a bad back and couldn't stand up in the garage any longer. I'll finish it off tonight but I am devoid of optimism. Assuming that doesn't work I'll order a new hall sensor module on Monday, but really this is just going through the (expensive) motions and exhausting all reasonable options before giving up on the bike.

By the end of next week I'll have tried everything you've tried with the exception of changing the loom. And I expect to have had as much luck as you.

 

[Dazlove]

s s s s s stutter again!

Gents

Sorry if you feel you have been left out in the cold but have had to wait a while to complete the next instalment.

As I have posted earlier, my 02 1150 is suffering the same probs.

I took your earlier advice (a bit previous as it happens) and bought an 01 ECU, which I have not fitted.

In previous responses you also queried the throttle bodies. I have also had similar thoughts, ie would very worn TB's cause a fuelling and/or electrical issue if there was excessive play on the butterfly valve/TPS interface. My TB's are absolutely donald (as in ducked!) with massive play on both right and left hand side. In fact I think the left hand one is worse, which makes me think that at the point of approx 30-40 mph on a feathered throttle, 2500-3000 rpm, would this excessive play cause the stuttering?

Anyway, I managed to purchase a pair of secondhand TB's (thanks Mr Sherlock) and, taking no chances, have had then refurbed (thanks Mr Scriminger) and they arrived back home this week. I have also ordered new cables with the intention of fitting them this weekend.

Hopefully this will cure the problem. If not, then it will have at least ruled out another option! I will report back in due course.

BTW, other than this really annoying glitch, she goes like stink and I really love riding her (almost as much as my 'busa (only joking!)) but as you guys have also inferred this problem is sufficiently bad to warrant a change of vehicle, which is a very sad state of affairs.

regards

Dazlove

 

[sproggy]

I wish you luck with the throttle bodies. Mine, after a mere 25k miles, were really badly worn for reasons I don't understand (possibly through incorrect adjustment - I've heard that having no slack in the cables can accelerate wear but I don't know whether this is true) and I changed them for a good second hand pair with very little wear. This made no difference to the stuttering - it didn't even improve it slightly. The only improvement was that the bike was quieter!

But at least I have a bike that stutters quietly now

How many miles has your bike done?

 

[Dazlove]

Hi Sproggy

She has covered 87,000 miles.

I do approx 3000 a month using her to commute.

These are the first TB's I have had to change, although I have had other 'big ticket' items. Gearbox rebuilt at 78k (thanks again Mr Scriminger!),clutch, paralever bearings and pins replaced, final drive bearing twice, left hand switchgear twice

Other than this she keeps running day in a day in all weathers, which, given our climate I don't think is too bad.

regards

Dazlove

 

[sproggy]

Well I guess the TBs didn't do too badly if they lasted 87k miles - I just wondered whether they'd worn prematurely like mine.

At what point did your bike start stuttering - did it happen gradually or suddenly? Had you just done anything to it (serviced it, replaced anything, washed it etc)?

Mine behaved like this when I bought it (big mistake - I thought it just needed setting up properly) so I don't know how it started.

 

[monkeyboy]

One of the TBs on my S made so much noise it sounded like a diesel - then the throttle return spring went one dark night too - rode home on one cylinder... still didn't stutter though

I'm sure this has to be fueling somewhere as it often feels like a slightly more gentle version of the shunting when you get to low revs. Perculiar thing is, after riding my S again now, my GS seems to have nothing like the engine braking of the S. It just smacks of clumsy fueling to me.

 

[sproggy]

Perculiar thing is, after riding my S again now, my GS seems to have nothing like the engine braking of the S. It just smacks of clumsy fueling to me.

Doesn't the S have higher compression than the GS? That would give more engine braking. I wish my GS ran like my S used to.........

I spent 2 hours flighting with the bike this evening - changed the FPR but couldn't get the front frame holes to line up well enough to get the bolts back in. Then the bloody thing fell of the centre stand and I had to jack it back up. Decided to drown my sorrows and try again tomorrow when I'm less pi**ed off. I wouldn't mind so much if it helped, but I don't have much hope.....

The way I feel now it might be on eBay tomorrow morning

 

[sproggy]

Finished doing the FPR this morning - what a bu**er of a job!

Anyway, took the bike out for a ride and it's transformed - from a lurching, stuttering nightmare..........into a lurching, stuttering nightmare with a new FPR.

TBH I knew this before I rode it - I could tell when I was doing the throttle balance that it was still playing up, the way it 'misses' a bit every now and then.

Time to order a new hall sensor I guess..................it's worth a (expensive) try, I suppose........

 

[monkeyboy]

Finished doing the FPR this morning - what a bu**er of a job!

Anyway, took the bike out for a ride and it's transformed - from a lurching, stuttering nightmare..........into a lurching, stuttering nightmare with a new FPR.

TBH I knew this before I rode it - I could tell when I was doing the throttle balance that it was still playing up, the way it 'misses' a bit every now and then.

Time to order a new hall sensor I guess..................it's worth a (expensive) try, I suppose........

Do a 'sale or return' jobbie with motorworks. That way you can do it free if it isn't the problem

 

[sproggy]

Do a 'sale or return' jobbie with motorworks. That way you can do it free if it isn't the problem

That only works on used parts, and the only way to tell for sure is to use a new one at £150. Once I use a new one it's not new any more. I think I have to go new or nothing. Nothing sounds good right now.

 

[Pekkavee]

Time to order a new hall sensor I guess..................it's worth a (expensive) try, I suppose........

You don't have to change the whole sensor plate.
You can change only the sensors ( Honeywell 2AV54 ) , much cheaper.
Look here
http://www.ebbo.org/2av54.php
Or fix the wire problem, look here
http://users.rcn.com/dehager/service/oilhead_hall_sensors.pdf

Pekka

 

[sproggy]

Thanks for the links. I've already checked the wiring and it's good. In fact the sensors check out in every respect and there are no indications of any sort that they've failed. They're just the final item on the long list of parts that might help if they're replaced.....but probably won't.

I don't think I want to go to the hassle of changing the individual sensors even if it does save money - I was aware that it's possible but reading the details I'm tempted to think that any job requiring the making of a special tool is probably a step further than I want to go.

 

[monkeyboy]

Thanks for the links. I've already checked the wiring and it's good. In fact the sensors check out in every respect and there are no indications of any sort that they've failed. They're just the final item on the long list of parts that might help if they're replaced.....but probably won't.

I don't think I want to go to the hassle of changing the individual sensors even if it does save money - I was aware that it's possible but reading the details I'm tempted to think that any job requiring the making of a special tool is probably a step further than I want to go.

Personally Sproggy I wouldn't chuck 150 notes at it as it's unlikely to be the answer. A 2nd hand one from Motorworks would be fine - they'll have checked it and if it is faulty then it's extreemly unlikely to exhibit exactly the same fault. I've changed mine and it made absolutely no difference. You can at least check it for nothing using them, and see what occurs. It's such a simple job (compared to the FPR at least) and only takes half an hour. Save you money mate for celebrations when you finally find the fault (or sell the bike)

 

[sproggy]

I came to the same conclusion - it's so unlikely to be the hall sensors that I'm not even going to bother with second hand ones. As you say, you tried it as a solution to the same problem and it made no difference. I've had enough.

 

[Dazlove]

Stutter

Gents

Have now fitted the new throttle bodies, complete with new cables.

Set up the TPS @ 365mV and synced TBs using a CarbTune. I did not touch the throttle stops but managed to get a very even, synced idle using the brass air screws.

Have since ridden her for approx 300 miles.

OMG........I cannot believe the difference! It is like a new bike. Despite the recent cold snap (I leave at 05:15) she starts on the button, no choke (I know its just a fast idle) and settles down immediately to a nice idle. This is a major change. Before, as the choke did not work (maladjusted cables), I would need to twist and release the throttle (like a demented Fuzeball Player!) to keep her running. Now, even though I still have no choke, as I broke the lever taking it off to replace the cable, she doesn't need it and idles just fine from cold. A new lever has been ordered though.

Next test was the awful transmission wracking stutter on an even throttle. I am pleased to say this is also cured.......hurrah!! Yes, I can feel just a hint of flat spot at this point, but the complete on/off bucking donkey has gone. I have even tried to encourage the stutter by feathering the throttle on and off, but to no avail. You can feel a very slight dull point in the fuelling, for a second, and then it is gone.

Also, I have noticed how quiet she is. Yes, the TBs don't clatter as they did, but at all revs she feels smoother and quieter. This I would put down to all components now working in unison.

I cannot believe how much one can put up with before any major works are contemplated. I wish I had done this a year ago.

I hope you find solutions to your woes but for now my faith in the GS is restored.

All the best

Dazlove

 

[monkeyboy]

OMG........I cannot believe the difference! Dazlove

Thats good news Daz - glad you fixed you fault. Do you want to come and fix ours I don't honestly think its the TBs on our bikes thats the problem - mores the pity...