Mods

An expansion chamber exhaust is the first thing on most folks minds I believe. Port matching the exhaust is a good idea as well. Don't try to make too many upgrades at once, if the bike doesn't run right after one upgrade, it is much easier to track the problem down. If you do 5 or 6 upgrades at one time and the bike doesn't run right then the problem is much harder to narrow down.

Here's a pic of one Sick Bike Parts

The other, if you take your exhaust off. You'll see the engine port is larger then the opening in the exhaust. Simply file or dremel the exhaust to match and polish it as best you can. You might not get them to match perfectly. Because of how the pipe is shaped, but that's fine the main objective is to allow the escaping air from the engine to flow as easily as possible. An easy way to do this is to shape your gasket to match the engine port, then use the gasket to mark out your exhaust.

I put my bike together today after I did some mods to the motor and rebuilding the bike. One of the Major mod's was trimming the piston skit for the intake and wow what a difference the motor is smother, more noise from the intake but that was expected. I was running to lean on the fuel before I haven't changed the c-clip in the carb and now I am running perfect, the spark plug is a brownish color not black or white. The motor is getting the right amount of fuel and air now.

I am also using a 1" long intake and I get crazy rpm's and their is more torque.

The 3rd link below is where you can see the difference in the piston skit and the intake, I hope Manic make's an intake that is 1" long because mine is on an angle.