Neosophist wrote:Yes.

If its' leaking air.. as described by your carb-cleaner affecting the revs you'll get inconsisten rich / lean mixture symptoms.

You'll also NEVER get a good idle.

Pilot screws back to standard and make sure you have a 100% seal on all the carbs before you do any investigating :-)

You'll get there.

Carbs sound ok.. just letting in too much air.

Is it possible to sort the seal on the leaking carb without taking them off and starting all over again?

This is turning intp a bit of a challenge to say the least!

oldgreyandslow wrote:

Neosophist wrote:Yes.

If its' leaking air.. as described by your carb-cleaner affecting the revs you'll get inconsisten rich / lean mixture symptoms.

You'll also NEVER get a good idle.

Pilot screws back to standard and make sure you have a 100% seal on all the carbs before you do any investigating :-)

You'll get there.

Carbs sound ok.. just letting in too much air.

Is it possible to sort the seal on the leaking carb without taking them off and starting all over again?

This is turning intp a bit of a challenge to say the least!

No idea, can't see the carbs from here.

If you look at the carb rubbers you'll see that they have a lip in them that the carbs sit into.. the jubilee clips need to be done up tight but not too tight else they'll squash and deform the rubber, there just to stop the carbs working loose... the carbs sitting in the lip does the actual sealing.

maybe the clips are too tight, or the carb is in at an angle, or the rubber isn't correctly on the engine.

i'd fully slacken off the clips on that carb and push firmly down on it, dont' hit it just lean on it with firm pressure for a few seconds, see if you feel the carb slot into place.

Neosophist wrote:
No idea, can't see the carbs from here.

If you look at the carb rubbers you'll see that they have a lip in them that the carbs sit into.. the jubilee clips need to be done up tight but not too tight else they'll squash and deform the rubber, there just to stop the carbs working loose... the carbs sitting in the lip does the actual sealing.

maybe the clips are too tight, or the carb is in at an angle, or the rubber isn't correctly on the engine.

i'd fully slacken off the clips on that carb and push firmly down on it, dont' hit it just lean on it with firm pressure for a few seconds, see if you feel the carb slot into place.

Its definetly a carb sealing/air leak issue.

I thought I'd got it all tight and sealed, in fact I reckon I thought this about 5 times today already!!

I'm not hitting them, straddling the bike and pushing down on the carbs, full bodyweight through palms of hands on the carbs but they don't seem keen to seal, the front carbs top clips don't fully engage in the slot in the rubbers very well.

Eventually I got it where I thought it was all sealed and tight

Started it, not easily on choke it was running at 2-3k and sounded rough, got it idling and sprayed carb cleaner at both front pots, revs rose dramatically in both cases.

Clearly the carbs aren't seating properly, or I should say I'm not fitting them properly!

Strangely it seems to be an issue with the fronts, not the rears

I've tried a few variations on a theme: Align the fronts, check from the side, it looks OK but it does seem as if the carbs dont need to sit very far in, then lever the rears in using two old dinner knives, sometimes the fronts pop out, sometimes not, I also tried tightening the clamps on the front before aligning the rears.

However it seems that tightening the front clamps pushes the carbs out.

Too much of the red rubber graese perhaps? Could overtightening the clips have deformed the rubbers too much to make them fit?

There's definetly no pop or whatever as they seat. Could all this repeated trying and removing have damaged the rubbers, or at least made them alomost too soft?

Its bloody frustrating to say the least

It sounds like the fronts are not fully engaged in the rubbers.
Is anything preventing them to go fully down, like a clip, clamp, hose, bolt on engine or carbs misplaced in the wrong position.

Are the fronts and rears in the same depth?

The clips should fit in the rubber grooves all the way round, if they are too low they will try to squeeze the carb stub out.
I have never had the fronts try to to lift out, they need some pull to disengage them.

Is the front carb rubber folding in, most likely the back edge, look with a torch and mirror.


Dave.

Sorted - I think

Took the carbs and rubbers off, replaced very carefully didn't tighten them too much, put upper clips on, made sure everything was settled in where it should be, put fronts in, the fact that the rears were now as far out as I remember them when it was a bastard to fit made me think the fronts were in good and proper, and they were, plenty of back and forth, checking etc, levered rear rubbers with my trusty dinner knives and voila in she goes. Lent on them for a bit, made sure everything looked about the right height etc. Tightened up the clips, not too much!!

Put it all back together and bugger me, it started fine.

Got it to a nice idle. sprayed carb cleaner everywhere, no change to revs so I assume no air leaks!!!

Blipped throttle, it returned a little slowly, almost hanging at about 2k befroe returning to idle, sounds like it may be a bit lean, now there's a suprise considering where this has been!

So turned the pilot screws just under a quarter turn out and it seems to be much better, blip throttle and it returns straight to idle, did it a few times, all good, let it get warm, still OK so I think we're on the right track

Thans to everyone who has posted replies, suggestions etc. much appreciated and I'm sure they'll be more to come. However tomorrow its time to put the plastics back on fill the tank with some nice fresh fuel and take it for a long run.

Cheers, I'm now going to have a beer or 4