I have a 94 froutrax 300 utility.If the throttle is pressed it wants to continue to idle high for a few seconds before returning to normal idle,it makes shifting aggrivating seeing it takes a bit to idle down.I disconnected the throttle cable from the carb and worked the throttle lever on the carb by hand and it does the same thing,so the butterfly is closing.I checked the boot and it has no air leaks,the carb is also clean.Any suggestions?

 

the slide in your carb sounds like its gummed up.

 

I have seen folks get a gummed up idle jet, and they turn the idle adjustment up to compensate. Eventually the gum may clear, and then it ends up idling to fast.

 

yeah, your round slide in carb that goes up and down isn't goen back down fast enought, may be the spring is getten worn out or the little clip came off, i would take the slide out and spray it all up with some carb cleanerr and make sure everything is together right and then try that

 

I found this evening someone cut the diaphram spring about 2 inches shorter so I replaced it with a new one and cleaned the slide,it did ok for about 20 minutes but started back,so the issue is in that area,I may replace the slide since it has lost the slickness it had.Moving it by hand it is sluggish returning down.When I had it out I rubbed it with some 0000 steel whool.You guys have put me in the right direction,Thanks!!!

 

Ok,I replaced the carb with a new one including the choke plunger as well as the choke cable but the problem still exist.Any other suggestions??

 

must be a crappy cable then

 

The ONLY way a gasoline engine can RPM is with an air leak. You have an air leak somewhere.

Slide hanging open.
Cable causing the slide to hang open.
Bad carb boot.
Bad intake gasket or other things.
I don't know where your air leak is? I do know you have one.

It's up to you to find out where.

 

check for a loose or cracked intake. make sure your air filter is charged and installed properly

 

Much thanks,the carb boot solved the issue