Bore or not to bore? That is the ?...

[DRTYMEX]

Received my 2003 yz250 manual from yammi the other day, disassemble and found out that my cylinder was score and piston shot :(.

Service manual clearly states that you CANNOT bore the cylinder. Took into work and the motorheads tell me you can. After that, took it to a local motorcycle shop, and he say it needs to be welded, bored out back to factory specs and nickle plated.

What's your suggestion for this newb here?

 

[viking20]

If there is deep scoring , the cylinder will have to be welded , the plating is very thin. You can get in touch with Eric Gorr / Forward Motion ( link on the left ) and probably have the cylinder bored oversize 265 cc or so. Maybe he will even have a cylinder ready to go on the shelf. The pistons will be availiable at a cost similar to a standard piston. FM can bore , plate and port the cylinder to your needs , for far less money than most other people , and it can very well be the cheapest option.

 

[Lorin]

For what Eric charges, you will get the cylinder bored and ported to your riding style for less than what most companies charge for just the plating. I had some work done on a previous bike and was pleased with the results of the 265 kit and all-around porting.

 

[DRTYMEX]

HMMM, how much are we talking about here? I was quoted about $200 just have it sent out from my local shop for it to be welded, bored and nickle plated...

 

[njrealtor55]

about $500 which includes porting.

not sure, but you may need porting once you overbore due to the angles on the ports that change whever you overbore.

either way, $500 for overbore, and porting is a great price. i paid $1200 for my race jetski just to have the cyls ported - the cases were more on top of that.

i plan on sending my cyl to FM when I get some extra $$. Big Bore should be fun!!! :ride: :yikes:

 

[viking20]

Dont forget , the 500 $ is including gaskets and a piston kit....