Blaster runs f***ing weird! Wtf?

OK So i found the problem.
I took the cylinder off and found this:
Looks like a broken piston to me.
stamped 0.25 (.25 over?) rings are ok
And WHAT direction does the arrow point, when i go to re-install new piston??
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i did not do the build. The wife really over rev'd the motor, forgot to shift and just kept the throttle wide open..
maybe that did it??

ANY idea where i can get a used piston?? i cant afford $50 for a new one, unless a shop wants to donate one, and ill slap a shop sticker on the plastics ;) hehe
 
you didn't hear anything? that should have been noisy as hell. I didn't hear stuff bangin around in the cylinder in your video. is the rest of the piston in the bottom end or what?
 
Overreaving wouldn't do that,so take it easy on her. lol It was probably out of tolerances. You need to measure the cylinder. Also how did the cylinder fair and what about the chunks in the crank?
 
The chunks apparently got ground up into little shavings. when i changed the oil i had a bunch of silver in it.
It was running fine till it got over rev'd, then i ran it low on gas, so maybe the combination of the two?

either way, i need .25 piston now, and ebay is $40 more than the dealer....:(

cylinder looks good, no scratching or scoring, looks normal. crankshaft looks normal
 
the trans oil isnt conected to the crank chamber at all. I think you got your blaster with that busted ass piston in it. i think it shattered the dude cleaned it out and put the f'n piston back in, otherwise you would have huge pieces of alluminum in the crank chamber. don't get any other piston than a weisco.
 
The top end doesn't mix with the oil so the silver in the bottom is something else. The overrevving might have caused it to happen sooner but it was on it's way and if you put the same size piston in it will happen again. You need to find the cause and not waste your $$$$$

Edit: Scott beat me....he has a good idea!
 
the trans oil isnt conected to the crank chamber at all. I think you got your blaster with that busted ass piston in it. i think it shattered the dude cleaned it out and put the f'n piston back in, otherwise you would have huge pieces of alluminum in the crank chamber. don't get any other piston than a weisco.
duly noted. :) Theres no pieces of anything in my crankcase, its clean as sh*t.
Weisco is good stuff, heard lots good about them
 
Yamaha Blaster Wiseco .010 (66.25)mm Piston Kit YFS200 : eBay Motors (item 200313736774 end time Nov-15-10 19:21:56 PST)

pretty good price. you will just need a gasket kit. you need to give the the guy you bought it from a piece of your mind dude. maybe a piece of your foot in his ass too! get the shop to hone if for you

Or i could spend $50 at the dealer instead of $80 at ebay, and egt the same stuff.
the gasket came off good, didnt even cook to the block yet. head came right off no prying to pulling no nothing, came right off
 
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Or i could spend $50 at the dealer instead of $80 at ebay, and egt the same stuff.
the gasket came off good, didnt even cook to the block yet. head came right off no prying to pulling no nothing, came right off

if you can get a weisco for 50 bucks buy me three. and reusing gaskets isn't the greatest idea. you can heat the head gasket up and reuse it but i wouldn't reuse the base gasket.