82 rm250z porting advive/ specs

You can pretty it up a little but it won't make it run better.

looking down at your intake, u can drill two boost port 8mm holes and make the port direct to the cylinder, back in the 80's boyseen did mine and a lot of national riders, you can widen the exhaust .5mm each side, I highly recommend laying the cylinder out with dye and scribe your port, u need to be perfect, If you speak with Gorr he'll want to install an 83/84 head he believes this is a better setup than full dome, I'm still on the fence with that thought. I raced this cylinder with raised transfers and exhaust also, depends on what power band your looking for.

Pretty fast bike stock, won Unadilla MX rewind twice with a stock motor, Personally I have been building motors for some 30 plus years saw a lot of different setups go conservative, the smart builders do the math before they put a tool to a cylinder, if you want to see a cylinder set up for porting look at the post 79 RM250 I recently uploaded

Eric Gorr is your friend and not super expensive.

Only choice is Eric, does Amazing work !!!

I have had both the 82 & 83, the 83 did like the 82 head for more hit but
it also had the timing retarded compared to the 82 model. Do both and
it does hit a lot harder but I felt less wheelspin on the 83 with its heavier
crank (which I liked), the 82 head is pretty picky on octane though,
which is one drawback.

I really liked a head I had done by R&D (Rudy & Dean), they cut a "pocket"
at the back of the combustion chamber that went into the squish area to help
hold the charge from the transfers for better combustion, then milled & reshaped
it to bring the compression back-this was my take on their explanation, it worked
great I do know that & much happier with pump gas.

There is a lot of room for blueprint work on the cylinders, most exhaust mods
would be pretty modest I would expect with the unbridged ex. port. At that time
I did not have any two stroke software to evaluate the porting, this is only an opinion,
but in retrospect, I feel there may be too much transfer port area which would need
epoxy to correct. Eric Gorr or Brent @ TDC? performance use this method. If
anyone you talk to want to make the already generous sized Boyesen ports big
enough to shove golf balls through....I would run away! lol