Is there any way short of not riding it to lengthen the life of the bore, rings, and piston? Would painting the piston skirts help? (with the right paint of coarse) I have had to rebuild ours going on 5 times in about 2 years. I keep the filters clean, and do regular maintance. I am waiting on our last piston for this. Its now bored 80 over and I'm going to try and bore it for the 105 piston. I'm about to the point of getting rid of it in favor of building a blaster framed 4 stroke 125. I know lots of guys that don't have to rebuild their 2 strokes as much as we do.

Any help would be nice.

 

What kind of oil are you using?

 

We get a year out of 1 piston.
I'm wondering about the oil also. It does make a difference.
A guy brought me 2 pistons that were run a year each. One was run on HC-1(??) and was wore normal I'd say.The skirt was dull. The other was run on Torco GP-7 (my personall favorite) and it was like brand new.Shiney skirt.
Ya don't have a crack in a air filter boot do ya?

 

I must be real lucky,or didn't put near the miles you do on my old LT80. I bought a very hard used 87 LT80, ran it about a year, did a .020 bore and rebuild, and my son ran the k-rap out of it for 5 more years, then I sold it to a friend, his kid ran it, then a couple years later, he sold it again. One rebuild from 87 to 2004, and that quad got ran ragged when I owned it, did clutch work, ported out the reed cage, put a pipe on it, and it ran like a charm for many years.

 

I have three years on my sons lt 80 with the same piston and rings. He trail rides it in the winter and dunes it in the summer, but doesn't race mx or tt or any sanctioned racing body, just dune drag racing

 

I'm using Klotzs (?) premium 2 stroke oil. I've also ran some Polaris 2 stroke oil in the past with the same results. The Klotzs is supposed to be some of the best 2 stroke oil around. (at least the best around me) And many guys that race is using it without problems. I've mixed it at 32:1 and usually add just a hair more oil to make sure its enough. We do ride alot, I mean when it is warm enough and we're able to , this thing runs a couple of hours every day. I check/clean the ail filter alot. I am sure theres no holes in the air box or boot going to the carb. I knew that this time around it would not last to long. The last time the skirt of the piston was worn and the rings was almost worn into on one spot. The bore was fine until I let my over zelous father help me hone it, and it opened it up to much. Right now I should get a new piston tonight and I'll have to take the jug and get it bored again. I just would like to get some more time on this thing before I have to do all this again.

 

Make sure and take the piston too the guy doing the boring. The cylinder should always be bored too the piston, and I would be concerned if the person performing the work did not ask for the piston.
Gary

 

The guy that does my machine work has always fitted the bore to the piston. He has built many high performance 2 strokes in the past and quite a good machinest. Thats why I'm waiting on the piston right now, so I can get it bored. I've used Weisco pistons and rings in the past, and I have no Idea who makes this big bore piston I've ordered. (I'd bet its Weisco, or their company anyways) I don't understand why its so hard on parts. Imean, I run my chainsaws under alot worse of conditions with out as much maintance and so far had no problems. (And its been used for years!!)

 

What's the bottom end like? IS there a lot of run out or wear in the lower bearings? Maybe causing too much movement of the piston in the cyclinder? Just a guess.

 

There doesn't seem to be any wear. I had wondered this myself, but it seems tight. How often do you engine builders replace the lower crank bearings? I hate to have to pull this all apart and split the cases, but I also hate having to redo this every 4-6 months.