My 85 Tri-Z seems to run well, but only at high rpm's. At an idle it will speed up and slow down. I have tried messing with the carburetor to no avail. I am by no means a mechanic and don't really know where to start now. When I'm riding it, it';s like it loads up and then finally takes off. Any experts out there? 85 Tri-Z 250, 99 Big Bear 350, 2001 Badger, 1976 ATC90, 1977 ATC110, 68 Trail 90

Make sure the float doesn't have a hole in it and still floats....Also could be the gasket between the cylinder and the carburater. Hope this helps.