Exhaust help?

[ronny]

Well Im not sure of my problem here, ive just recently went throught my r motor, new clutch little things, had the cylinder off crosshatches all seemed well. I've ran it for a few weeks so far all was well, now it seems as though its starting hard, it still runs perfect, I dont see a difference. It use to start first 2 kicks everytime and now its only every 10 to 12 or so and half on the time it has a backfire but once shes running I can't see any difference, but i noticed a rather large crack/hole where the paul turner mounts to the frame and was wondering weather this would effect whats going on, its about a dime sized hole in the second piece of a paul turner race pipe where it mounts just about where the motor mounts are,
Thanks
Ronny