need some help

[jayhedrick]

ok i was riding today and heard a ping :whoa: and then the engine cut off.. i knew instantly what had happened.. im glad it did not happen right before the triple!!!!! anyway, so after a lot, and some more cussing.. i took the head off and there she was... and big chip out of the piston with a bit of the ring actually above it... it messed up the cylinder... so my question is do they make sleeve kits for my bike or do i have to purchase a jug along with the top end kit??? the bike is a 02 yz125... i looked a bit on various sites but did not come up with much.. so i figured one of you guys would know right of hand.. thanks

 

[_JOE_]

It may be more cost effective to go to a 144 big bore.

 

[_JOE_]

"YAMAHA YZ144 BIG BORE KIT
Fits 1999-2004 Yamaha YZ125, ported NIKASIL 144cc cylinder by Eric Gorr of Forward Motion, piston and gaskets. BUY
NOW $475 Ground freight, continental USA $10"

From Eric Gorr's garage sale items.

 

[jayhedrick]

that would be sweet!!!! but i was wondering if i could just get a sleeve for like $80 have my cylinder bored for the sleeve then get a new top end kit?

 

[_JOE_]

Sleeves were over 100 I though. Labor to install it is probly close to 100. Another 200 to bore/plate it. Gasket kit is 35 or so. Piston kit is around a hundred. Now you're at 600 dollars. I'de save a few bucks and get the cylinder you know is done right and will run much better than stock, but WTF do I know.

 

[Red Pinger]

Get it replated. $200 Forget the sleeve.

 

[jayhedrick]

i forgot to mention that i use to work at a machine shop and im good friends with the guy that owns it so the machine work i will be doing for free or hardly any cost at all.. so im thinking that is the right way to go

 

[_JOE_]

I'm pretty sure the piston rings are meant to be run against a plated bore. You might have isseues there, I don't know for sure. The best bet as far as reliability and longevety is to have it replated by a reputable plating company. This isn't something you want to cheap out on, it will cost far more to do it twice than it would to do it right.

 

[jayhedrick]

ohhh i see where your coming from now.. i will check to see if it needs to be plated and if it does i will just replaced the cylinder then... if not i might try the sleeve way.. im glad you mentioned that so i didnt go messing things up worse than they already are

 

[spark250]

Dude, why wouldn't you get that big bore??? Even if you did sleeve it and the machine work is free you won't save but $150!!!

BTW is this just a general labor kind of machine shop or do they specialize in engines?

Cuz there is a big difference. It could turn in to a real pain if you don't have the correct fixturing and tooling. boring bar etc... And it really helps if the person has installed a sleeve multiple times. It's not a great feeling to have someone (no matter how talented a machinist) learning how to do something on your motor!!!

Might save you money in the long run!

 

[Rich Rohrich]

Even if you can get a machinist to install a sleeve correctly they aren't likely to have the right angle die grinder (or the specific knowledge and skill) needed to fix the transfer ports, and chamfer the port edges after the sleeve is pressed in.

If you go the sleeve route you'd be much better off by dealing with a company that specializes in this type of work like La Sleeve www.lasleeve.com.

That said, sleeves belong in lawnmowers not race bikes. ;)

 

[jayhedrick]

Dude, why wouldn't you get that big bore??? Even if you did sleeve it and the machine work is free you won't save but $150!!!

BTW is this just a general labor kind of machine shop or do they specialize in engines?

Cuz there is a big difference. It could turn in to a real pain if you don't have the correct fixturing and tooling. boring bar etc... And it really helps if the person has installed a sleeve multiple times. It's not a great feeling to have someone (no matter how talented a machinist) learning how to do something on your motor!!!

Might save you money in the long run!

no its a machine shop that does just engines... even while i worked there there was countless sleeves installed so thats not an issue at all... if i had all kinds of money laying around i would do a big bore belive me i would... but i have all kinds of payments that come before a big bore kit... i would rather have the bike back on the track rather than sitting in the building an extra month or so waiting...if this post comes across as me being an ass im not dude... im just trying to get back on the bike fast and with what i can afford...