Originally Posted by mwolff
Glad to have found this thread. I just bought this '86, pretty clean with 25,000 miles from the first owner who seemed to take care of it. Now after starting it, maybe 100 times, and a good 40 mile ride in the Natl. Forest, I need some advice on how to make it run better. I have gotten the starting routine down, and it has never failed to start after 3-4 kicks, and it idles perfectly, but then runs kinda rough at speed. It seems to have plenty of power, doesn't backfire, just runs rough as the RPM's climb. I adjusted the valves, they were pretty loose, and changed the plug, it was old but looked like it was burning fuel properly. Do I tear into the carb for a rebuild, or just clean. BTW, the air filter looks pretty clean also. Anyone's $.02 would be good. Now, can I post the pic.? Nope, I'll go to SmugMug and re-post.
I replaced the Carb Diaphragm on Mine and she runs 100% better! mine is an 88 XT600 2KF model. the carb diaphragm is not cheap ( cost me 70 quid, about 130 dollars) but as part of a carby rebuilt that cost about 200 dollars total!
Worth every penny. Starts second kick, 60mpg, pulls like a TRAIN! ( especially now i have gearing better too 14 tooth front and 39 tooth rear)