Thought I would mention this. My chain line isn't perfect and with the stock 415 chain it would catch on the teeth of the sprocket occasionally. I would notice this when I would walk along side of the bike with the engine off and the clutch lever in. Then I got a #41 chain and now the chain runs perfectly with the sprocket. This is because the chain is a little wider and compensates for the chain line. Now when I look at the chain line from the rear of the bike it looks perfectly straight.