Anyone want to guess what happened?

[blastapole]

Well I cheesed the engine riding sunday. I havent taken it apart yet but I'll tell you the conditions and what happened and Then we will see who's right...lol

Ok normally I run 32:1 premix. Sunday I decided to go 40:1 with new amsoil. I was using yamalube and before that mobil1. It was about 95 degrees Fahrenheit outside. I ride it for about 10 minutes just warming it up and goofing off in a field. Then I wanted to race the 250x since i put a 14tooth sprocket on the front. So we race and it beats me by about 2 quad lengths but I could tell the blaster was running faster/stronger than it has before.

I takeoff on the second race and in about fourth gear the bike loses all power and dies, I pull in the clutch and it sounds like a soda can is being crunched in the engine. It wont kick over.

I'm gonna try to pull it apart this weekend.

Anyone want to guess?

 

[03blasteryfs03]

is it locked up

 

[ATVkid2002]

cyclender or pistin blew... just a wild guess

 

[blastapole]

yeah its locked up. I'm trying to be optimistic and hope that a ring stuck or a reed petal broke off and got wedged.

 

[REEDracing94]

reeds or piston broke apart

 

[tcoop474]

if the kick starts stuck u f*cked the crank up bro. if not rings or reeds

 

[Jay]

Time for new top end an bore,maybe crank.

 

[Jay]

They do run strong right before they blow.

 

[diesel]

Your lower rod bearing let go, causing the piston to hammer the cylinder head <--- Makes a sound like beer cans rattling around in the engine.

 

[Awk08]

that sucks, deisels prognosis sounds good, but i stick to my original thoughts, piston skirt broke off, and went down in the bottom, wedged against the case by the crank

 

[ajames942]

If its wedged, you can be pulled like 30MPH by a truck and put it in first and dump the clutch, I'm sure whatever was wedged in there, won't be anymore!!! lol

 

[03blasteryfs03]

or it throw a rod

 

[blastapole]

Well took it apart today and the skirt broke off on the exhaust side.

awk guessed it.

yay.

 

[joedirt5724]

lower rod bearing. id be almost willing to put money on it.

 

[matt75]

sh*t mines been broke down for two weeks waiting on parts.. I had the same problem he did and putting it back together now... How do i know if the rod bearing is shot..? It turns and everything fine.. but it does have a little play in it, but i cant see no problem with it.. My piston skirt broke off too.. Dont take much to freeze it up..

 

[Awk08]

yeah awk guessed it, because thats exactly what happened to mine, and it acted the same way, most of the piston was chewed up and found in the pipe, but there was a few larger chunks in the case, and one kept catching between the case and crank, when turned by hand, but the shop kept telling me my crank bearings were gone, so i got a new hot rods crank anyway, just in case there was any little peices in the bearings, but after they did the rebuild, they told me the crank was still good,
i got $60 for it on ebay
wasnt there some kind of prize for guessing right???? hahahaa

 

[joedirt5724]

well if the rod bearing is shot the rod will be locked tight on the crank. u can tell if its going bad by the amount of play the rod has on the crank. its gunna have some side to side play, but if u pull up and down and it moves that is a sign saying crank needs rebuild fairly soon.

 

[natureboi47]

okay so i am going through this right now and I have read this thread and have checked my crank shaft, it has play side to side but no up and down play does that mean the crank is still good, and if that's the case what would have caused the piston to break??? any help would be great thanks guys

 

[blasterKILLER]

you def got piston in your bottom end

 

[stephen12091985]

if it has no up and down play then ur good.could have been caused by piston slap