I am currently studying mechanical engineering at university in England. At present I am carriying out my 3rd year project which is based on a variable goemetry two-stroke exhaust system.
My test bike is a 1992 Yamaha YZ 250. I need some info on the port timing of this bike. Exhuast and transfer port. Can anyone help me with this or perhaps point me in the direction of somebody who might be able to help?
Ideally I need a full technical specification on this bike including all the specific dimmensions of the ports as well as the timing.
I would do a search on the net, but most likely your not gonna get this info on a site this this. try emailing pro circuit or any major engine company dealing with porting and such on dirt bikes. I would imagine that they would need these specs in order to resleeve and machine the cylinders and head for performance reasons