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Discussion Starter #1
I'm new to the forums and so far it looks like it has lots of information. I look forward to reading more and possibly contributing in the future.

Now bear with me as i don't know that much about small engines. Being a polaris owner i've spent much more time riding than fixing.

I drive a 96 sport with the 400 2 stroke. My dad bought a scrambler last spring and one day he suggested a little drag in the field to see how they compared. I hit it pretty hard off the line, but that is pretty normal for me. As i got going i believe i heard a clunk(it was a while ago) and then the back tires locked up and i came to a skidding stop. I put it in neutral and it rolled fine so we dragged it back to the yard. I tried the pull start and i couldn't get it to turn over. About a week later my brother was around and not knowing about the break down he hopped on and he said it fired right up but ran rough so he shut it off. Since then it has sat since i didn't have time to tear it apart.

I plan to work on it this winter but in the mean time i would like to hear what you guys think it might be.
 

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First off, welcome aboard!
 

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Discussion Starter #4
I'll be sure to try that but unfortunately the quad is back at the farm so i'm out of luck for now.

Without doing tests, is there any number of things it could be? Right now i'm just looking for any guesses.
 

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Discussion Starter #6
I took my sweet ass time but i finally tore into it over the last couple days. I was talking to a guy i know and he said it sounded like something called cold seizing. We tore the engine apart and sure enough the piston is all buggered up and there are some chunks of it missing somewhere in the bottom end. The cylinder walls still look good and i didn't drive it after the breakdown, so assuming that the crank is okay, how much am i looking at to get it running again, that is if i can find parts.
 

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wiseco complete kit piston rings circlips wristpin and top end gaskets, is like $130 or so if thats all you need you better look everything over real good if parts of your piston are missing
 

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Discussion Starter #8
I talked to a buddy today who knows a lot about machines of all kinds and he recommended using an oem piston cause aftermarket ones can cause problems. Didn't really make sense to me. He also suggested i get the cylinder ball honed even tho it looks really good.

Also while looking around i found a company called Aaen performance that has a stage 1 performance kit. New pipe and muffler, 38mm TMX carb and boysen reeds. It offers a pretty decent power gain, but i'm concerned about the age of my quad and wondering if its too late for upgrades. Any suggestions?
 

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I have been using wiseco in my race bikes forevever and never had a problem. they are very reliable and tough. Its never to late to upgrade either. Polaris stuff is expensive and really no better than wiseco. you should really just get the cylinder bored and buy an oversized piston that way any minut knicks and stuff are removed for sure and wont cause compression problems down the rode. also make sure you break the motor in properly when you finish it. That is critical to haveing your motor work last along time otherwise you just wasted alot of time and money. Take your time and do it right!!
 

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Discussion Starter #10
Alrite, thanks a lot man. The biggest thing holding me back right now is lack of money. Hopefully i can get a decent summer job to pay for this.
 

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Discussion Starter #11
I've looked pretty close in the bottom end and even got a magnet down there but i can't seem to find any pieces of the piston. I do recall seeing a couple pieces fall out of the exhaust when i removed it. Is it possible that it was all sucked out?
 

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A magnet isnt going to pick up pieces of aluminum piston. You should take the motor out and make sure there isnt anything in there. It doesnt cost anything and if your going to do it, you might as well learn how to do it right. Your whole rebuild could be for nothing if there is a piece you missed down there. Better to be safe then sorry.
 

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you can also try to blow down in crank with air hose hold one hand over hole to see if anything blows out. but best way is to take motor off if your not 100% sure.good luck.
 

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just take the motor apart. If just one tiny piece gets into that crank you will have a disaster and have to do it all over again. best do it right the first time. All youll be out is a couple of gaskets and you shoudl replace your crank seals while you have it apart because they go bad alot. there only like 17 a piece so its worth it. just take your time clean everything and do it right and youll have a good motor for a long time.
 
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