does anyone make a big bore kit?

[seamonster]

Does anyone make a big bore kit for GG 2 strokes. I was thinking of going up to a 300 kit this winter but didnt know if anyone makes them. I know I can get the factory oem parts to do it but they are ungodly expensive through GG. Any information is appreciated....

 

[Rick]

do a search....plenty of guys have made 250 into 3hundo!

 

[lankydoug]

It's just a matter of swapping the cylinder, piston (with rings of course) and head...all else is the same.

 

[seamonster]

I understand how to do it, but I was wondering if any aftermarket company was selling complete kits. I know I can get GG parts but dont feel like taking a second mortgage for a 300 oem cylinder.

 

[lankydoug]

I understand how to do it, but I was wondering if any aftermarket company was selling complete kits. I know I can get GG parts but dont feel like taking a second mortgage for a 300 oem cylinder.

If you're not in a hurry you could pick up a used cyl. and head from a part out and get the cyl. plated, then buy the rest new. I have an 03 EC200 that I was thinking of putting a complete 250 or 300 engine in someday. My plan was to buy an engine and take my time going through it. The problem is my 200 just might last forever, I suspect it has had an easy life.

 

[Brian]

Looks like Eric Gorr offers a 265 kit. Piston might be very expensive.
http://www.eric-gorr.com/bigbore250.html

You would think you could get a 250 cylinder bored out to be a 300 cylinder but maybe they are different...

 

[ECRider]

Check this past thread out.
http://www.gasgasrider.org/forum/showthread.php?t=7328&highlight=250+oversize+piston&page=3

There is a 275 conversion you can do to a 250 with an oversize Wiseco piston built for the TRX250R Honda quadracer.
I was thinking about this mod myself seeing as I have already had work done to the head & porting of my EC250.

 

[hannesd]

If you're not in a hurry you could pick up a used cyl. and head from a part out and get the cyl. plated, then buy the rest new. I have an 03 EC200 that I was thinking of putting a complete 250 or 300 engine in someday. My plan was to buy an engine and take my time going through it. The problem is my 200 just might last forever, I suspect it has had an easy life.

are those 200's that bullit proof?
i'm thinking of getting one if i can get a real good deal on one out here, since i don't ever use all the power i have in my 300,not even half of it!

 

[noobi]

are those 200's that bullit proof?
i'm thinking of getting one if i can get a real good deal on one out here, since i don't ever use all the power i have in my 300,not even half of it!

They modify the 250 engine to make the 200, so everything is over engineered for an engine thats only 200cc. So they are pretty tough, the member Stainlesscycle got something like 800 hours out of the stock piston with just ring changes before the piston broke from fatigue, and it was raced.

 

[GMP]

Best way is save the coin and look for OEM parts. Its engineered as a 300 with the right port timing, and the 250 power valve parts drop in with no worry about clearing the piston.