tri moto 125 bad rings?

[jnollet]

Hey everyone. My new problem is that my bike is smoking pretty bad and has low compression and no power. I am planning on replacing the rings because I am pretty sure they are the culprit. When I looked online, I noticed that there are different size rings for this spcific engine/ piston. What would be the reason I would need a 1st , 2nd or 3rd alternate part instead of just purchasing a standard set? Should I get my cylinder bored out and use a bigger ring (alternate rings previously mentioned) Also, if I do use these bigger rings will i get more power out of engine? Thanks.

[thefox]

As the cylinder wears it ovals out, when it wears beyond spec. then you need to bore it to the next size making it round again. With the larger bore size you will need the corresponding piston and rings.

What do you do?
1. Get a repair manual
2. take the top end apart and measure the piston and cylinder
3a. If they are in spec. then buy new rings of the proper size (the previous owner may have bored it before so check the size stamped on the top of the piston to know what size rings you need).
3b. If they are out of spec. then take it to a shop and have them measure it and tell you what size piston and rings you need, then buy the piston and rings and have them bore it.
4. Put back together and run it.

[leokendall]

Have you ever done a compression test on it, are the top end gaskets blown?, Find a compression tester and test the psi. Also tighten up the cylinder head bolts.

Since your bike is a 2 stroke, bad rings will not make it smoke like a 4 stroke with bad rings. 2 stroke bike/engine will put of a lil smoke no matter what good or bad rings. Check to see how much you are mixing your gas. To much oil and that lil puppy gonna smoke like crazy. What colour is the smoke? White, water in your gas, Black to much fuel, Blue to much oil.