replacing piston and rings?

[Rabbitist]

does anyone know of any good guides to follow for this? my 2000 250ec. its my first stripdown and rebuild?
any help welcome lads cheers luke

 

['11EC300]

Maybe this will help, I have never done it yet but plan to when the time comes
http://www.youtube.com/user/RockyMountainATVMC#p/c/A14890CE79ACFAAC/25/-FFIWtqU5Zc

 

[gasser]

Use envelopes or small plastic bags to keep bolts and screws separated and identify them on the package.

The small nut that secures the upper end of the power valve activation rod must be heated before removal. If not the stud that it screws on will very likely break off.

When you pull the cylinder off cover the crank well with several layers of paper towels so nothing can drop down inside.

 

[Dude]

It really is very simple to do. If you need help, feel free to drop me a pm and i can walk you threw lots of it via phone.

 

[Rabbitist]

brilliant guys thanks im thnking as im getting a bit of blue smoke the rings are worn..?

 

[bchatt]

Um, it is a 2 stroke so you are putting oil in the gas, right? The blue smoke is because of this oil, all 2 strokes produce smoke.

 

[bossmans kid]

I would do a compression test with the engine warm before I tore the bike down. If you have to rebuild the top end, make sure you don't put the new piston in backwards. The gap on the piston ring goes on the carb side. Also make sure to use the new piston pin clips. The opening on the clip should be either up or down. If it faces toward the front or rear of the piston it has more probability of popping out from the force of the piston going up and down. I like to coat the rings and skirts with engine assembly grease before I put the cylinder on. When you are bolting the engine in the frame, you will have an engine mount on the head. Make sure you torque the head before putting this mount on. When you put the head to frame mount on, tighten it to the head first and the frame last. I also mix my first tank with petroleum oil for a faster break in.

When yuo pull the cylinder off, have a machine shop check the bore for taper and round. If you have to send the cylinder to a chrome shop to be re-nicked, let them know what clearance you want, probably .0020, but that is just a guess, I'm sure someone on the site can give you a more educated measurement than I can. Also, never send the wrist pin bearing to the chrome shop, you will never see it again. Good luck.