250r w/ Aftermarket 300 Head

[Popeye]

Hey ya'll, my buddy gave me a pretty decent parts bike with the motor. The bike is an 84 (I guess the motor is too) and it is a 250r bottom end with an
aftermarket 300 head that was supposedly made for the 250r. Does anybody know anything about these? I'm assuming it adds a little bit of power. How much? What carb should I put on it? It's also missing the rod and piston, so I'll have to buy them. Any advice on that? Buddy said I need to go get it measured. I have to get it honed and cleaned up anyways. I really just want to get a better idea of what I got and what I need to put on it.

Thanks for any advice.

[Flossyb20]

The head alone will not make it a 300...you need the cylinder, piston, and head to make it a 300....as far as I know (someone speak up if I'm wrong) the only 300 kit available for these is a Hondaline, not aftermarket. If you can find an OEM piston for the set-up, go for it, otherwise a piston out of a Kawasaki 650 jet ski is a direct swap. With that set-up you could go with a 38mm Air Stryker....and be very pleased

[Popeye]

Thanks for the info. That answers a lot of questions I had. I really didn't have any idea what piston or carb to get so thanks for taking the time to answer that for me.