Gasket for your pocket bike?

what is the purpose of the gaskets? I recently installed the performance exhaust and didn't put back on the stock gasket. What will happen if I don't put on the gasket? would it cause gas or air leak or other problems? Thanks!

it pretty much seals it up. helps it not leak. you will probly have alot of oil run out between the exhaust and exhaust port.

what is the point of those plastic parts that go around to the back part of the engine and cover the gasket and part of they exuast pipe??

cause it just seems usless and in the way

its pretty much a shield so you dont burn yourself... i dont have any platic on my engine anymore.