Ummmmm.... Hello?

[Brauap]

I know this is the 250R section, but I was told to put this here.

I just bought a 2002 Yamaha YZ125, and I did a compression test and it was around 65psi. So I tore it all apart (motor) and I found out that the cylinder was and pistion where scatched. This is my first dirtbike, as is 2 stroke. I have been told I have to bore it out, and get it re-coated with nicicel and all that.. ( I will post pictures of the cylinder later)

But, would I/should I just buy a used cylinder, new pistions, rings, gaskets, and o-rings? Or should I get it bored, honed, coated with nicicil, bigger pistion, gaskets and o-rings. I am looking for the cheeper method. I found this on eBay:

www.cgi.ebay.com/ebaymotors/Yamaha-YZ125-2002-cylinder-with-stock-bore_W0QQitemZ220231923702QQcmdZViewItem?hash=item 220231923702&

Here are the pictures:

http://i197.photobucket.com/albums/aa283/braaup/100_1990.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1991.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1992.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1993.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1994.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1995.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1996.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1997.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1998.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_1999.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2001.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2002.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2003.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2003.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2005.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2006.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2007.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2008.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2009.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2010.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2014.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2012.jpg

http://i197.photobucket.com/albums/aa283/braaup/100_2011.jpg

[Master LTR450]

cheaper method would be to buy a cylinder probably, but the better method would be to have it re nikasil and honestly it probably wouldnt be too much more and you would have anew cylinder basicaly

[312R1]

The ebay link didn't work for me, but it would most likely be cheaper to buy the one on ebay.

[Brauap]

Or, do you guys think that I could just get the nikicil and fill in those scratches? and then I won't have to bore it out any?

[Master LTR450]

its all one process really, you cant just bore a nikasil cylinder like a steel sleeved cylinder

[Brauap]

huh?
don't bore it, just fill in the scratches with nikasil, can you do that?

[stever250r]

I think what he is saying is...... 2stroke race bike cylinders are coated from the factory. You can not bore a 2stroke dirt bike cylinder like you can a steel sleeved cylinder like the trx250R

You have to have the cylinder sent off.. the coating stripped and then have it recoated.

You can not just bore and hone it.

[Brauap]

Oh. yea I knew that. I thought he was saying I can't bore it out. And I was like why.. but any whom... ( wow that was gay. :rolleyes: ) how long do you think the total process would take, and how much it would take. Thanks!

[regg187]

You could get the biggest piston that the cylinder will take and have the cylinder bored for that piston and then send it off to have the nikasil work done, just find out the thickness of the nikasil coating and consider that into your clearences when having the cylinder bored. the bigger piston will give you a power boost over your buddies with a stocker, it will be slight. and unless you plan to race in AMA or other major series, the extra cc's really won't matter at the local level, since it s a 2002 I'm sure your not going for the supercross lite title next year!:)