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How bad is bad

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So I got my 02 for $1100 thinking i'll just throw some valves in it and have sweet bike for cheap. Well like always after further inspection, it needs some things. The kid I bought it from "claimed" he put a piston in it, and by the looks of it, i highly doubt it. The main problem is the fact that the end of the rod has some score/pitting marks on it. I know the RIGHT thing to do is replace it, but i'm broke and alread have like $400 invested in the head. Do you think i can get away with just putting in a new piston rings and wrist pin? here are some piks let me know what you think...thanks

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Always cracks me up to see how big the piston is on our 450's

Cyl looks good but dont know about the crank Good luck on it thou

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it is a good idea to replace it or else you will be replacing a whole new top end soon when that rod starts slapping around off that wrist pin and blows everything to smithering! depending on how bad the inside of that rod is, you could get away with it until another valve adjustment but ur probably gonna be replacing a new wrist pin and probably a piston from the wrist pin being slapped around. fromthe pics it looks bad but its hard to tell, urs eyes can see deeper cougues then you can feel. i feel you about the broke statement. i just bought my 450's, sent one end over end 4 times and need to replace my rear subframe and yosh pipe. kind of sucks cause i dont have the cash right now... hopefully this helped a little. take it easy man

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The cross hatching looks good onthe wall, piston skirt not too bad. But hey weight the risks.... You have the head off and things accessible it would be good to change them. A piston, ring and pin should be ok. Do it now for piece of mind.

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get a new piston just put the old one in a friends bike the piston broke and detroyed the cylinder it is not worth the time to put the old one in

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your crank is gone... get a new one. in a not too distant future, your piston WILL turn the wrong way in the barrel, if you choose to keep running that crank.

oh, and that piston looks worn out too...

Sorry :/

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I was def. goin to replace the piston rings and wrist pin, my concern was the rod. The pin is very snug when assembled so it doesnt show any signs of loosening up. Guess i'm just trying to avoid the obvious...it needs to be done :thumbsup:

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A few hundred now, $3000 plus if it grenades. Its your bank account.

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Measure the id of the connecting rod and check it against the spec. If it's out, just replace it. Like others have stated, it will cost you alot more in the long run if left alone. I just replaced a 250 and 450 crank with the same problem. The cylinder looks to be in good shape but that piston should be replaced. Better put a timing chain in too.

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I wouldnt run that rod.

You can get a rod kit. That will save you some dough over a whole new crank assembly, but the mains and lower still need attention.

Id save my pennies up and put a crank in it. Its easier to do in a thumper than it is in a two stroke believe it or not. No special tools or anything. It just slides in.

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The rod doesn't look all that bad to me. If you said it doesn't have any play in it with the wrist pin installed then u might can wait it out till the next rebuild but its up to you. Like everyone else has said if it does blow..... Thats some major money. But i think i might would take my chances and try it with the new top end. Its your call man let us know how it ends up

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So I’ve decided to just go ahead and completely overhaul this thing, being that the balancer shaft bearing has some play in it as well. I found a bottom end kit on eBay for $280 that includes crank assy. All bottom end gaskets, oil seals, and bearings. It says 04-07 should fit 02 correct?

http://cgi.ebay.com/ebaymotors/WISECO-COMPLETE-BOTTOM-END-REBUILD-KIT-CRF450R-CRF-450_W0QQcmdZViewItemQQhashZitem3efcf3273eQQitemZ270531766078QQptZMotorcyclesQ5fPartsQ5fAccessories

I’m shocked it’s that cheap, too good to be true? Crank, with new piston and some other odds and ends total runs to about $440. I’m going to get the cylinder measured up to see if that’s still good, if not, tack on another 200 to that price. So for around $650 I get a basically new engine, and worry free riding. Not to mention the experience of splitting the case. By the way shawn mc you sure the crank just slides out and you don’t need a case splitter or crank installer? That would be sweet since the tool costs like 60 bucks. Wish me luck

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