Right Cylinder Running Hot + Backfire 1100GS
 

1998 R1100GS

Right cylinder seems to be running hotter than left. I've noticed this when riding in sandals (Yes - I know!). My right foot gets REALLY hot. Seems to be a bit more heat discolouration around the RH intake too. Riding in boots I don't notice.

Also, the engine is backfiring a bit on the overrun. It may be the crappy Nepali/Indian petrol I'm using. I'm presently up into the Himalayan foot-hills too.

Otherwise - it's running well. Did valve clearances and synchro'ed TBs so it goes very well. Plugs are in good nick and the right colour. Oil is fine and running at normal temp on the gauge. Throttle cables properly seated.

Is this heat problem normal? Is it related to the backfiring? Is there nothing to worry about?

Can't comment on the misfire, but if you look carefully you'll see that the right cylinder's further back than the left due to the crank journal arrangement. This is what's causing toasted toes, nothing sinister (haha).

Regards, Mick

hello,

I've had lots of backfires while riding in central america, I mostly noted it at altitude. I blame it on crappy/ low octane fuel. the moment good grade fuel was avaiable, the misfires were gone.
have a good trip,
MARK

Thanks People.

Yeah - had noticed the right cylinder is further back. It's still hotter though. The engine bar on RH side is way hotter than left side.

Take the point about the poor petrol. Only seems to have been backfiring since did valves/ TB synching. Got them spot on so don't know why it should be so.

Also - took fuel tank off and it's possible I may have re-connected fuel lines wrongly. Would this cause backfires - if wrong amount of fuel going to each side?

Hey Buzz,

I told you the backfiring is not normal ;)

Check if there is air getting into the system through or besides the rubber collar between the injection pump and the cylinder. I had it a couple of times so far when my old collars wear out.

Do it soon, otherwise you will risk a piston seizure, I was told.

You can have a spare collar from me if it fits.

Regards

Lars

I'll look into it Lars. ta.

Rubber collar was loose so tightened the fixer. Seems to have improved things.

Well done Lars. But tell me, why didn't you suggest this when you were actually SITTING on the back of my bike 2 weeks ago and commenting in your precise teutonic tones on the unpleasant backfiring that was spoiling your pillion ride as you flirted with the local Nepali girls?

Explain that one.

Well, problem got worse and worse but now it's SORTED.

The rubber collar on RH intake was loose. When I synched the TBs it must have been a bit loose so although got the synching correct - there was too much air coming in on RH side.

When I tightened up the collar - synching was way off again. Borrowed some vacuum gauges and got it spot on now.

No more backfires - runs perfect.