You need to run the dog **** out of it one good time to really clear the bike out. Mine will spray out the silencer if I'm just putzing around, not really running it and my jetting is just a size fat and I run 32:1.

Plus, it's a 2-stroke. You're gunna have oil spooge on it unless you're running some crap walmart oil at 100:1 "cause race bike".

Drill out the rivets and use a nut and bolt if you have to. Go buy a rivet guns from autozone for $20 and you're set for as long as you own this bike.

For the leaky flange and coupling, use the copper coat rtv silicon stuff. Apply generously.

Go run the crap out of the bike.

Also, make sure you don't have too much oil/air filter recharged spray on your filter. That'll choke the engine.