giant flat spot at highway speeds.

Im back on the bike. The problem is more defined now. Ok, so only at highway speeds above 55mph the bike does a seesaw hiccup deal between 3-4K Rpms. While this is going on, if I pull in the clutch and let it coast and rev up the engine back up to 3k it goes up to 3 and then it slowly dies and kills the engine. Anybody had this one? Is it wind? Vacuum fuel cutoff valve? Thx!

Have you bypassed the vac. fuel valve? It's about 10 minutes to remove plastic and 5 minutes to by pass the valve. Don't forget to plug the vac. hose. Go ride and come back and either hook it back up or put the plastic on and be done.

Haven't tried it. But will do. I put a shield around the carb outlet hoses under the bike and it seemed to help a great deal!!! I think we are approaching a "solved" here.