Tickover suddenly lumpy - should I be worried?

[Rabbitson]

Noticed this morning that the tickover is a bit more unsettled than usual, nothing too serious but I am a bit concerned as it has always been good as gold before and this seems to have happened very suddenly.

I have been riding through all the crap in the last few days and I gave the bike a jet wash last night, also I forgot to switch the choke off for about 10 miles this morning!!

When I started the bike up this morning I didn't really notice it (although it never runs wonderfully on very cold morning anyway), and like a tired Friday morning plumb, I forgot to switch off the choke for about half the journey.

Those things considered, I guess it could be salt or water somewhere in the electrics, or too rich fuel, but, the bike seems to run fine apart from the tickover and after I switched off the choke, I still did about 15-20 motorway miles before I had to stop, and only then did I notice the lumpy tickover

Read various horror stories on this board about burnt valves, exhaust back pressures and so forth, so wondering if this might be a warning for something serious.

Bike has a Laser can (not sure if it's a full system but as there's no cat I guess it is), not sure if it has the chip, but BMW dealer has serviced it and repaired it over the last four months so hopefully, they would've noticed if it wasn't set up right.

Any thoughts? it's a 95 1100

 

[John Armstrong]

If it won't run at all happily then a check of the throttle cross over cable and that it is seated properly might cure it. Its like a push bike brake cable and goes from LH to RH (I think) throttles. If the cable comes out then the bike won't run or accelerate properly and coughs and bangs away as the LH anf RH pots try to kill each other.

HTH.

 

[(RIP) Kaister]

i 'think' the 'choke' is actually just a fast idle lever.
What it does is let more air in to cope with the extra fuel being delivered - due to temp sensors telling it it needs extra fuel.

more air + extra fuel + cold temp = stoichometric ratio in the cylinder head = correct mixture = more revs.

you won't do any harm leaving the lever open

Phil

 

[Smartbazza]

lumpy running

is it getting the correct number of bars on the rid? I use mine all winter and found the bars were varying on the rid - makes the electronics confused. Easily fixed if this is what`s happening,

 

[boxer]

i 'think' the 'choke' is actually just a fast idle lever.
What it does is let more air in to cope with the extra fuel being delivered - due to temp sensors telling it it needs extra fuel.

The 'choke' is a fast idle lever but it operates by simply pulling the throotle cables to each injector a small amount. Just enough to increase the revs and to hold them off idle for a fast tick over. As far as I know this is purely a mechanical set up involving the throttle cables and rpm. It does not effect the mixture as such.

If you operate the lever you can see the pulleys on the side of the throttle move a small amount. At least you can if they are adjusted OK

Russ.

 

[Rabbitson]

is it getting the correct number of bars on the rid?

Can someone translate this for me?

David

 

[John Armstrong]

RID

Can someone translate this for me?

David

Assuming its a 11 / 1150 GS: Oil temperature gauge on the Rider Information Display (extra cost option on German bikes) standard on UK. Uses ten segments to display the temperature of the oil going past its sensor. Normally about 5 in the sensible bike riding months.

 

[wessie]

I had something similar. I had raised the tank to get access to the battery so that I could fit the lead supplied with my Optimate.

When I started the bike it ran very rough. I found that the plastic outer part of the throttle cable on one side had lifted a little. It had come out of the guide and snagged on the top (this is at the bottom end of the throttle cable).

Effectively the 2 cylinders were getting different amounts of fuel as one throttle was opening a little more than the other.

It was a simple job to fix - just put the throttle cable back into the guide.

 

[Rabbitson]

Sounds suspiciously like the throttle cable might be the problem. Had a quick look at it and it seems the plastic piece that protrudes out from the control block has a crack down its length. Couldn't therefore completely get rid of the problem, but moving it around it the cracked holder to what felt like a more 'seated' position did seem to help.

Will attack it with some glue tomorrow and see if that totally rememdies the problem.

Thanks for all the advice, that would've taken me ages to figure out!!

Great, hooray!

David