1150GS idle issues

Hello Chaps,

First time poster here, so forgive me if I have skipped a few posts or cant find other posts relating to my problems.

We have a 2004 (I think its 2004) 1150GS (single plug per cylinder) with around 130 000km on the dial, and the only aftermarket add on is a performance pipe from Cowley

Ok, here's the back ground: The bike hasnt ridden for most of 2021. If it did 100km it was a lot. The battery was kept on charge (occasionally) and the motor was occasionally started to let it idle for a bit.
Of course, this is not the ideal situation.
Recently we have decided to give the bike some more miles and have started to ride it again. But the tank of fuel that it was parked with was rather dirty and the idleing started to play up.
I added a fuel/injector additive with a new tank of fuel and sent the bike around the block a few times to run it through the lines and injectors.

I also removed the tank to add a permanent charge lead to the battery.....

Saturday the bike had a significant reduction on power whilst out on a long ride. The Mrs made it to the venue we were meeting at (bike limped in) and we couldnt start it again. I removed the plugs and checked for spark either side which it had. I noticed the left plug was wet with fuel, and the right plug was dry.
We trailered the bike back the next day to be safe

From what I have read up on the net, it seems it could be a culmination of a few thinigs - so any help and pointers to help me further would be great please:
Note, I havent started to check anything yet as these are just idea's for me to check: I also assume the right carb/injector is clogged up and this is the reason why the right plug was dry

Check the left & right fuel cable to make sure it has not been dislodged/unseated by removing the fuel tank
Check the BBS are at 1 full turn out, if not then balance these
Check the stretch in the fuel cables and remove any slack, make sure these are also the same tension to either carb
Clean the air/fuel filters etc
Remove the injectors and clean/replace back
Dont fiddle with the TPS as I dont have a GS911 tool

Is there anything i am missing? Or is this generally a good place to start

Dont ask why the bike stood for almost 12months - we had way to many expeditions on last year...

Thanks in advance for tips and advice

Check the left throttle cable hasn't become unseated also.

Sent from my SM-G986B using Tapatalk

Will do that too - thanks, I'll add it to my list to check

This ...

... is what you're looking for; very common if tank has been lifted

Thanks Obs, its going to be my #1 item to check tomorrow evening when I'm at the bike again

when was last time fuel filter changed i would start there and when in there check the small u bend pipe bet its got a split in it.

Martin James said:

We have a 2004 (I think its 2004) 1150GS (single plug per cylinder) with around 130 000km on the dial,

Click to expand...

2004 model should be a twin spark...

Martin James said:

I also assume the right carb/injector is clogged up and this is the reason why the right plug was dry

Click to expand...

Swop the injectors over and see if the problem moves with the injector.... or just pull the R/H injector out of the throttle body and see if squirts fuel when turning the engine over.

@ ynot - I'll add that to the check list, thanks. Cant honestly remember when last the fuel filter was changed (I know, bad dog Spot)

@ Steptoe - Thanks, I'll certainly pull it to see if it is pulsing, and if needed I'll swap it to the left bank to see if the problem moves.

I'll add the checks to the list

Thanks Gents, for the help so far

Well, as you were correct, the right throttle cable was unseated. Obviously very quick to pop back in. I did try and start the bike but it coughed and spluttered and back fired a few times without any meaningful idle.

The throttle cable on the right though was very slack which I'll sort out to match the left side on the weekend

Any other pointers I can look out for? I'll do the other checks above on the weekend when I have more free time.
And Ive read somewhere about resetting the computer system by pulling #5 fuse, wait 5min then put it back it, turn on the inginition(no start) and swing the throttle twice to full open. Switch off, then switch ignition on again to start bike. Is this correct or should i not bother to reset this?

Given that the bike had a 'significant reduction in power' on a ride suggests that at the start of the ride it was fine. Plus, you have a dry plug on one side.

Therefore I'd be far more inclined to look at fuelling issues. I'd inspect the injector as Steptoe suggests, then move to the fuel filter.

I would leave the ignition well alone until you've exhausted all fuelling possibilities, or you'll risk introducing another variable into the issue.

Martin James said:

Well, as you were correct, the right throttle cable was unseated. Obviously very quick to pop back in. I did try and start the bike but it coughed and spluttered and back fired a few times without any meaningful idle.

The throttle cable on the right though was very slack which I'll sort out to match the left side on the weekend

Any other pointers I can look out for? I'll do the other checks above on the weekend when I have more free time.
And Ive read somewhere about resetting the computer system by pulling #5 fuse, wait 5min then put it back it, turn on the inginition(no start) and swing the throttle twice to full open. Switch off, then switch ignition on again to start bike. Is this correct or should i not bother to reset this?

Click to expand...

Make sure the throttle cables are seated correctly on the pulleys and both butterflies open at the same time when you open the throttle otherwise it will never run properly. If the cable has become unseated it may also have done so in the boden box (junction box where the cables meet under the battery tray) crack the throttle open fully & rapidly a couple of times with the ignition off but check the visible sections first to make sure they're properly routed and looped around the throttle body pulleys correctly.

BMW manual, if any use?

Next page

The Other PaulG said:

Given that the bike had a 'significant reduction in power' on a ride suggests that at the start of the ride it was fine. Plus, you have a dry plug on one side.

Therefore I'd be far more inclined to look at fuelling issues. I'd inspect the injector as Steptoe suggests, then move to the fuel filter.

I would leave the ignition well alone until you've exhausted all fuelling possibilities, or you'll risk introducing another variable into the issue.

Click to expand...

Thanks Paulg - You are correct in the loss of power and dry plug on the right. The throttle cable was unseated on the right which I replaced. I also noticed there is a lot of slack in the right cable whcih I will adjust. I'll also make sure the cables are seated/running correctly too.
I agree, ignition is the last thing I will check.
Thanks fo the tips

hops said:

Make sure the throttle cables are seated correctly on the pulleys and both butterflies open at the same time when you open the throttle otherwise it will never run properly. If the cable has become unseated it may also have done so in the boden box (junction box where the cables meet under the battery tray) crack the throttle open fully & rapidly a couple of times with the ignition off but check the visible sections first to make sure they're properly routed and looped around the throttle body pulleys correctly.

Click to expand...

Will do, thanks Hops

Cook1e said:

BMW manual, if any use?

Click to expand...

Will be of great help, thanks Cook

Really handy seeing problems and how they are solved on here.

Sent from my SM-G986B using Tapatalk

As I mentioned earlier in the thread @tristafarian, I'll update it over the weekend when I have more free time to have a look at the bike.

The response to my queries so far have been of great value to me to isolate the issues I have on the bike. Thanks to all the contributors.

Yes mate, just saying how useful it is to me as a fairly new GS owner seeing the problems and their solutions. How the collective knowledge comes together.

Sent from my SM-G986B using Tapatalk

Tristafarian said:

Yes mate, just saying how useful it is to me as a fairly new GS owner seeing the problems and their solutions. How the collective knowledge comes together.

Sent from my SM-G986B using Tapatalk

Click to expand...

Agree 100%, or people kind enough to not let us bang our heads against the wall expecting different results