I bought a Polaris Trail Boss 250 with bad rings about two months ago, put in a new piston, rings, and wrist pin. Didn't replace the bearings, I'm a rookie.
Its been running good ever since the new piston and rings, except it was making a knocking sound, I was told recently that it was from not replacing the bearings. Is it too late to pull it apart and replace just the bearings or will I need to have it bored and a new piston/rings/bearing/wrist pin put in as suggested by a friend.

Additionally, it will not run at the moment after a day out in the trails, it kept flooding itself, and would die on idle. Other than that it ran fine for about 6 hours then wouldn't start. It was suggested to rebuild the carb, but I've read you may do that multiple times with no change.

Ideas? Thanks much!

 

Welcome to the forum! It's hard to get by on a 2 stroke by just replacing with a stock piston and rings with out first checking what size the cylinder is and if it needs to be bored out to the next over size. Plus the rod bearing and crank bearings are high wear items also and on an older machine it's best to usually to do a complete rebuild. Some people can get by with just sticking a piston and rings in,but usually most can't. Best to take the engine down and have the cylinder measured along with installing a new rod kit and crank bearings. Probably not what you want to hear,but I've seen this a lot over the years. OPT