on my 94 sportsman 400 2 stroke my piston skirt broke. i have cyinder at rick ritters. i have found most of the pieces in my pipe when i took it off. i do not have any leaks in crankcase when i poured gas in it to check for leak. i do not see any trash in crankcase. it turns over freely with hand. i have flushed it several times with gas. if it were you would you go ahead and take rest of motor apart to make sure you get everything out or just go with it. my bike has about 2500 miles on it. also when i drained gas out of crankcase just metal flakes came out first not any chuncks of piston. this would be a fine time to go ahead and replace water pump sean and bearings if needed thou. just like some feadback on this one

i had also talked to rick about this today and he said if it were him he would go ahead and tear it down because small particales will get stuck behind bearings and you cant flush them out. this is probably what i will do just to be safe but that sure is alot of extra work.

Rick be the man....safe is smart!!!!

Maximuc
I had the same problem with my 96 400explorer(same motor)about a year a go.I didn't do a complete rebuild,i just flushed really good with gas,and rebuilt the top end(bore,piston,andrings).At the time I had a little knock in the lower end,but I thought just a upper would take care of it,WRONG.I just got finished(tonight) rebuilding the intirer motor top to bottom.It wasn't that big of adeal.I got all my seals,and gaskets from Rick (105.00) hell of a deal.She runs SWEET now,I wish I had rebuilt her last year.

If you wiggle the crank by hand and feel any slack,or hear aknock in the bottem chang it now and save you some time later.

P.S. Rick knows his stuff,and his parts are great and priced wright.

I had the same problem and I chose to just flush out the bottom end myself. I think it also depends how long you're planning on keeping your '94. If you're going to hang on to it then be on the safe side and tear it down. It's been 2 years and I've had no problems but it's really just a gamble if you take the shortcut method. I'm getting ready to replace my top end again and I'll be checking the crank out real well. So far I've been lucky I guess.