Re: Master Links
With proper chain alignment and tension master links will not cause you any problems. I agree with Aleman. You have a chain alignment/tension issue. If the master link is hitting the engine case and causing interference, then the chain is not properly aligned.
View your chain path from the rear of the bike. It should be an absolutely straight line. If it is being pulled to the side then there's your problem.
Rough teeth on the sprockets can also cause chain problems. Smooth the teeth, especially on the rear, driven sprocket so the chain rides evenly over them and doesn't bind anywhere. I like to use wire brush on a bench grinder or a metal finishing pad on a side grinder to take any roughness off the kit supplied sprocket teeth.
Drive chains also need lubrication. Either a good motorcycle chain lube or chainsaw chain/bar lube is good. Make sure you don't have any rough/binding links in your chain. The kit supplied #415 chain is notorious for having rollers and cheek plates that bind.
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