21-10-16, 05:29 PM
It'll likely be a blocked pilot jet if it runs ok on throttle but not at idle. It's happened to mine twice now. Of cause you'll want to go through and clean all four once you have them out but you can find the culprit by starting it from cold and, running at idle, feel each exhaust down-tube. You'll find three heating up and one much colder. Obviously after a minute of running they'll be too hot to touch so you have to do it strait away.
You can reuse the carb seals if the look fine and you're careful removing them.
You can reuse the carb seals if the look fine and you're careful removing them.