Im not good a working on bikes im trying to learn. My bike is hesitating or missing at cold temps and recently backfired kn excel before warming up completely . Any ideas on where to start?

 

I'm guessing your bike is carbed? First check the intake gaskets for leaks. Where the intake connects to the cyl heads. Start the bike and spray wd 40 around the flange and listen for idle change. If it changes then it's leaking. Next. Put a 46 slow jet and a shim under the needle jet , turn the mixture screw out 2 1/2 turns. Do a search on the forum for tried and true carb mods and you will find more info. Do not buy an expensive carb kit.

 

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