carb synchronisation

[agbrindle]

I've been trying to sort out the carb synchronisation on my '91 R100GS. However, I have no luck getting the vacuum guage readings to be anywhere near the sameon both sides. The right hand one seems to be at least double the left hand at tickover, and when I take the revs up to say 3000 rpm, the right hand one increases but the left hand one stays more or less the same.

Any ideas?

 

[mikyh]

Carb setup

You have to sort the idling and midrange seperately.

Idling is controled by the throttle stop screws and mixture screws.
midrange by the cable adjusters.

The carb which gives more mixture and pull stronger will give weaker vacuum reading!!!!!

And of course some experience in balancing carbs goes a long way. Try and try again till you'll get the hang of it.

Myself, I no longer use my makeshift gauges, only my ears and feel. Smooth, round sound at Idle, smoothe transition when opening the throttle. At half throttle and more it doesn't matter anyway.
Miky

 

[cookie]

ensure slack in cables

set mixture screws to factory settings

do the idle first with the throttle stops

move the mixture screws a small amount each way & set to best running. repeat previous step if necessary.

then open the throttle slightly & get the guages equal by adjusting cable adjusters

it's a knack, but not too difficult.

 

[TZOLK]

A similar thing happened to me. Turns out one choke/enrichner circuit was stuck open.

 

[sorebums]

All of the advice above assumes that your carbs and jets are clean, there are no air leaks round the rubber manifolds and that the diaphragms are without holes and are correctly seated on the slider and around the edge of the vacuum chamber.

If your diaphragms are 14 years old, I'd check 'em.

Simon

 

[v4our]

All of the advice above assumes that your carbs and jets are clean, there are no air leaks round the rubber manifolds and that the diaphragms are without holes and are correctly seated on the slider and around the edge of the vacuum chamber.

And the valve lash is set to spec.


Trevor