Whats a Reed - Seriously i dont know

There inbetween the carb and the intake port of the motor. The compression the motor makes forces then open and closed to let the air/gas mixture into th motor. They are like a valve on a 4 stroke if your familiar with that. Basically they let the air/gas mixture into the motor so it can run.
 
ohh ok there the 2 stroke version of valves ok i understand, but why dont 2 strokes just have valves then ?
 
because a 2-stroke intakes and exhausts from the ports on the side of the cylinder. plus 4-stroke style valves would be unnecessarily complicated. There are a few designs that use a valve but it is down in the crank case.

blaster induction 101:
the gas oil air mix hereafter called simply fuel is first sucked through the reed valve as the piston goes up and the windows in the piston line up with the intake port. and then falls into the crank case lubricating the bearings. then as the spark plug fires and pushes the piston downward the reed valve snaps shut, the fuel pushes up through the transfer ports into the upper cylinder both from pressure from the piston coming down and from the suction created from the exhaust leaving the exhaust port. As the fuel rushes in and replaces the exhaust the oil in the fuel also lubricates the cylinder wall. Then the piston start back up and the process starts over. This is just the basic theory behind it as I understand it. It is really much more complicated relying on timed pulses from the expansion chamber and reversion and port timing and various other things that are beyond my understanding. hope that helps clear things up a little
 
Great answers guys, and nobody was a weinie to the kid.The reeds are made of various materials. Carbon fiber, fiberglass, and when I was your age they even made them out of stainless steel. Reed valves also are different stiffness, and some are "two stage" I'm sure there must be something on the net that would show and explain two strokes and four strokes better maybe with pics.