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TTR600_marc 21 Apr 2008 05:21

Carb sync symptoms?
 
I've had the carbs on my '98 TTR600 taken out and cleaned. Now at around 1/4 throttle (at slow engine revs pulling a high gear) the engine 'hunts' a little. It is responsive when the throttle is snapped open and runs great at higher revs with more open throttle. I was wondering if the secondary carb could be set to open a little too early, causing lean mix (not enough vacuum to lift the slide but butterfly still letting in air). I am confident the carbs are clean and needles and jets were not adjusted.

Any ideas?

Marc

aukeboss 21 Apr 2008 05:39

Not easy
 
to diagnose these things, but I seem to remeber something comparable with my TTR 2002 - to be solved by setting the idle mix correctly (if smbd cleaned your carb and did not remove the idle mix screw, he did not do a good job).
Screw at standard setting - heat up engine - turn out till revs increase, keep turning out till they decrease - screw in 1/2 a turn - leave it. Re-adjust idle speed.

Auke

TTR600_marc 21 Apr 2008 07:40

Quote:

Originally Posted by aukeboss (Post 185728)
Screw at standard setting - heat up engine - turn out till revs increase, keep turning out till they decrease - screw in 1/2 a turn - leave it. Re-adjust idle speed.

Auke

Thanks, I'll try the idle jet screw first (best to start with the easiest things!). It is set it at standard 3 1/2 turns out now but I think it was something like 4 turns out before dismantling.
Marc

TTR600_marc 22 Apr 2008 03:08

Quote:

Originally Posted by aukeboss (Post 185728)
I seem to remeber something comparable with my TTR 2002 - to be solved by setting the idle mix correctly Auke

I tried idle mix adjustment but no change to the symptoms. :(
Since it runs fine at higher speeds I assume it is unlikely to be a rubber boot problem - is that correct? Any other ideas?
Marc


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