Got a two year old stock Scrambler that started running weird. Took it to the dealer who diagnosed it as a stuck piston ring. Had to bore it oversize to repair it. I am surprised that a well maintained oil injected machine running on Polaris lube oil would fail after less than 50 hrs on it. Anybody else have these problems?

 

Well, just do a search on the word piston in the Polaris forum. I think about everyone with a Scrambler 400 has had piston problems at one time or another. I'm in the process of replacing mine.
Seems the stock pistons are prone to failure. It seems to me they were bad enough to warrant some type of recall. Put in a Wiseco and you won't have the same problem. If your dealer put a stock piston back in, good luck.

 

I'm another Scrambler owner with a replaced piston. I had modified the engine and scuffed the piston.
When you have it apart you may want to get the cylinder ported and the head reworked.
When it goes back together, you may want to pre-mix some oil in the fuel to help keep that new piston alive.