intermittent cut out whilst riding R1150 GSA Twinspark

DrFarkoff · Jul 9, 2018

I have used the search and there are a plethora of threads shown

If anyone has a link that they found this fault with I'd be grateful of a pointer in the right direction

Situation is that when riding at a steady 3000 rpm when hot the bike runs fine but if you try to accelerate ... When the revs hit 3500 it coughs all engine power is lost and when you shut the throttle it comes back online

Its is very F***ing disconcerting and I am not too proud to ask for help

Bike has just had a service new plugs etc as "this" was not the fault I was looking for originally :blast

But apparently it had been doing this too :blast

I am going to finish doing all the things I normally would do in this situation but I have NEVER come across this fault before!

Its like the engine just shuts down and until you move that throttle it won't fuel or fire up again :confused:

Ignition loom is fine
Coil sticks are new 1200 type ones
Plugs are new
Fuel Filter is new
End float and Valve clearances checked
TPS set correctly and reading through the range
Also had new Hall sensors last year

mspenz · Jul 9, 2018

Can you take it out with a GS911 plugged in? Is there an alarm ? Do you have a spare TPS and Hall to swap and try ?

You'll figure it out :thumb2

DrFarkoff · Jul 9, 2018

Yup I "think" I did, As Sherlock Holmes said if you eliminate the probable then you can only be left with the improbable!!

Methinks an issue with the ECU

as the story developed there was a new lamda probe fitted and it ran fine and then it just started bollixing about and this was apparently the second new lamda probe

So after I had done everything else and watched the GS911 live data and decided to disconnect this new lamda probe

Bingo It all works!

Could possibly be some sort of conflict with Greek tuning chip (Which I also just found out was fitted in there!!!) and a lamda probe!!!!

Test rode and it ran fine IN fact it ran very very very well because I had been over every fecking thing there is to be over! :rob

mspenz · Jul 9, 2018

Interesting stuff, maybe worth contacting Greek John to see if he has had any other similar issues with his chips. Good job.

hops · Jul 11, 2018

I had similar symptoms, turned out to be the ‘U’ shaped pipe from the fuel pump (inside the tank) that had a number of small cracks in it. It looks fine from the outside but the walls inside crack and fail under pressure.

daveg · Jul 12, 2018

I had a similar problem on my 05 GSA. I tried all the usual things to find the fault. Eventually I went to see Steptoe and when he plugged me in to the analyser found an intermittent fault with the TPS. I replaced it and it's been fine since.

DrFarkoff · Jul 12, 2018

hops said:
turned out to be the ‘U’ shaped pipe from the fuel pump (inside the tank) that had a number of small cracks in it. It looks fine from the outside but the walls inside crack and fail under pressure.

daveg said:
I had a similar problem on my 05 GSA. I tried all the usual things to find the fault. Eventually I went to see Steptoe and when he plugged me in to the analyser found an intermittent fault with the TPS. I replaced it and it's been fine since.

Thanks for the input folks in the end

Had a new fuel filter fitted and the pipework closely inspected, Had my known good TPS fitted with same result

Bike is now touring around Cumbria and the lakes with (lamda is disconnected Greek Johns chip still fitted) no reported issues, the fella had bought a spare ECU and was going to get me to fit it until he rode the bike :green gri

and he liked it :aidan

Looks like a conflict between the ECU and Lamda probe in some form (Even checked the cabling from Lamda back into the loom

stevebrooker58 · Jul 12, 2018

Lambda sensor wiring routing

Hi ,
Just read your post and found it quite interesting as I have had very similar issues changed stick coils for the newer type still had the problem.

Tried the unplugging of the lambda sensor ran like a pig.

I did some browsing and apparently there was a recall for re routing the lambda sensor cable away from the HT leads , the small metal clips , as it was found in some cases the HT cables were interfering with the lambda sensor signals.

It worked for mine.

Steve

Nin · Jul 12, 2018

DrFarkoff said:
So after I had done everything else and watched the GS911 live data and decided to disconnect this new lamda probe

Bingo It all works!

Could possibly be some sort of conflict with Greek tuning chip (Which I also just found out was fitted in there!!!) and a lamda probe!!!!

Test rode and it ran fine IN fact it ran very very very well because I had been over every fecking thing there is to be over!

Interesting - I had exactly the same issue with my SE, as soon as I disconnected the Lambda probe it ran fine. I did try it with and without the GSJohn chip and Lambda connected, but noticed no difference.

sykospain · Jul 12, 2018

There should perhaps be a sticky of a very simple flow chart for people to follow in the event of the bike firing up OK but then running rough or as in Dr.F's case, cutting out and / or hesitating / hunting.

Last month in my case when the Rockster arrived on the truck into the Barcelona shipping depôt from Manchester, courtesy of the impressive 'eurobiketrans', the cause was simply a corroded ignition stick coil. Fit replacement bobina, borrowed from a nearby 1200GS awaiting a service in the workshop - bingo. Lovely zoom-zoom.

My local bike mechanic José, who knows these oilhead motors very well, says it's either the fuel filter / pump / U-rubber or it's the bobina in the cyl. head. Which he says should never have been crammed into a roaring hot, narrow tube right on top of the spark plug.

But Dr.F's fault being finally narrowed down to wiring induction conflicts is v e r y interesting, as Arnie used to say on the Laugh-In.

https://www.youtube.com/watch?v=Fnab1TdehFs

West coast gser · Jul 12, 2018

So £20 odd quid for a U shaped piece of rubber !!! could a U not be made from a piece of metal pipe stainless or ally ? and still work the same ?

DrFarkoff · Jul 12, 2018

West coast gser said:
So £20 odd quid for a U shaped piece of rubber !!! could a U not be made from a piece of metal pipe stainless or ally ? and still work the same ?

Needs to be flexible so you would still need two rubber slip joints to join it to the fuel pump and filter

intermittent cut out whilst riding R1150 GSA Twinspark

DrFarkoff

Grumpy Ole Git!!!

mspenz

Well-known member

DrFarkoff

Grumpy Ole Git!!!

mspenz

Well-known member

hops

Well-known member

daveg

Well-known member

DrFarkoff

Grumpy Ole Git!!!

stevebrooker58

Member

Nin

Well-known member

sykospain

Registered user

West coast gser

Well-known member

DrFarkoff

Grumpy Ole Git!!!

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