Started my quad and got a suprise as the revs ran up to the limit right away. stroked the throttle several times to see if throttle was stuck ,not. it settled down after about 30 seconds. did this again about a week later.
I think this is a case leak or a intake manifold leak. anybody else?[img]i/expressions/face-icon-small-frown.gif[/img]

 

Start your quad and take WD-40 or starting fluid and spray it around the intake manifold and case and listen for a change in RPM. If RPM's change you know you have a leak.

 

When it does this, grab the choke. If this settles it down, then u have a very lean mixture at low revs. Either you have an air leak or your carb settings are too lean on idle. To me it sounds like an air leak. Like rockrider said, spray wd around the base gasket and head gasket and around the carb setup. If there's no leak, then try adjusting the air screw. Richen it up and see if that helps. If u have an air leak this wont help. My zilla did this when i bought it. DO NOT RIDE IT ON A LONG RUN. Mine got very very hot and spewed the radiator fluid everywhere. I was very lucky i didnt blow it. I found that i had a stripped base stud that holds the cylinder down. It was letting the cylinder rise a little and letting in air. We re-tapped the hole and shes as good as new. It idles fine now.

 

Actually I have leaned it down at idle as i could not get it to idle. I took the carb apart and cleaned it out once. Right now I have the idle mixture screw at 1 turn out with the idle stop on the slide turn all the way in. It loads up really bad at idle and 1/4 turn so I am thinking air leak. Havent done a compression check yet but that is on the list.

 

Best thing to do is get your local shop to do a pressure test. Your engine may have alota compression but still have a leak. The shop will pressure test the engine by sealing the exhaust port and the inlet port infront of the carby boot. They then test to see at what pressure the engine will hold. They can find the source of the leak for you too. Just pray it isnt the case. Its a pain in the butt! [img]i/expressions/face-icon-small-smile.gif[/img]