Okay i have a 2007 TRX450ER and it wont idle. I have cleaned the carb. checked the air filter. Now it got hot and was low on coolant but i filled it up. It didnt run very long. The idle adjustment screw wont do anything for the idle. I set the jets in accordance with the service manual. A friend says it needs a vlv job not too sure. It does sound pretty rough with a slight knock but has always had that. No aftermarket parts, all stock. It starts and runs with choke but ran it for 10 minutes and then took the choke off and it died in about 1 minute. Need help. Please. New to the site and this is the test drive. lol