section8joe
XS650 Addict
I have a david bird hardtail with 4 inch stretch. I've been getting a weird shimmy/vibration at around 55MPH. If I go a bit faster it goes away and I can't feel anything below 55mph. I don't think its an out of balance tire because it's not a constant vibration. It seem to be more along the line of the chain rotation vibration. I've checked my valves, synced up the carbs, re-adjusted the clutch, check both wheels bearing, Steering head and brake drag. I think the problem may lie with my monster craftsman chain tensioner. I have the chain tensioner mounted kind of low and the skate wheel tension kept flipping over. I made a new swing arm part of the chain tensioner that's about 1.5 inches longer then the stock one. I'm thinking maybe it's not getting the snap that it should to keep the chain tight. I hear they sell a beefier spring. I also have been reading about "harmonics" and that this may be something I may just have to deal with. Can someone suggest a solution?