sticking carbs

[maxico]

The carbs on my z900 stick at 3000 rpm when the throttle is closed. After a while they will drop to idle speed but this can take upto 20 seconds or so. When moving they can sometimes be induced into dropping back to 1000rpm by going down a gear with no throttle.
Are the throttle slides getting stuck. If so would a drop of redex/wd40/oil be of any help. If not has anyone got any ideas???

Thanks.

[davejames]

Sounds like you may have an air leak on the inlet side. Are the carb mounting rubbers ok ??

[Pigford]

Maxico, buy some 'easy-start' and spray around inlet rubbers with bike running. If revs rise, the rubbers are leaking
BE CAREFUL NOT TO DO IT STRAIGHT AFTER A LONG RUN WHEN THE ENGINES VERY HOT :!:

[MaineKZ]

Maxico
Does sound like an airleak.
Another thought: I 've experienced throttle slides being 'sluggish' to seat down on my KZ1000. This occured after an overly enthusiastic cleaning session when the K&N filters took on quite a bit of moisture. I made the mistake of leaving them damp and this caused some fine corrosion in the sliders/slider barrels during a lay-up. Stripping the carbs to clean this corrosion up is a reete pain so try squirting some good stuff around first see if it frees them up.
Also it's always worth checking your throttle cables to check they're returning the butterfly crisply. Amazing how many times cables are at fault.

[Bruce Sexton]

If the sliders are sticking try cleaning the bores with Autosol and check the sliders for any pits.

Bruce

[maxico]

Carb holders didnt look too bad but replaced them anyway.
Sliders moved quite nicely but gave them a tickle with the autosol just to be sure, but she still sticks religously at 3000 rpm on the way down. A quick flick of the strat/off switch and she drops down to tickover. I note someone else has the same problem.Will try some of the tip given in this later question.
Thanks.