I cant believe she didnt blow...

Well I got an 05 Crf450R Motard for about $1500 from a guy knowing that it wasnt well maintained, and that i was gonna need to go through it but it was a steal anyways. Got it back to the house gave it a once over kicked it and it started idled and I killed it. The next day got into the tear down. This motor was def a whisper away from exploding... Opened the oil drain plug and about 200-250cc was left. From the looks of the piston and head she was feasting on oil. Cant wait to order parts wednesday and get it back together!





Bottom of piston scorched


Upper half of conrod also scorched


My next question is that there was def a little skirt wear on the cylinder but it dosnt look to bad and running a finger you cant fel anything nor is there any marring anywhere else in the cylinder. You guys think its ok for a hone and reuse?




looks like the crosshatching or whatever its called when there made in the first place...id think ud be fine runnin that

Honestly, none of that looks like it was too bad...I htink the con rod comes that way stock.

The real tell is the wrist pin and wrist pin bore on rod....which neither look absolutely destroyed...

If I were you I would be checking the crank seal.

That burned look could be from burned oil. The piston looks nice as well as the cylinder(40 hours?). Measure the cylinder and the rod for size/out of round. The piston pin looks real bad, hopefully the rod doesn't. The crank comes blue around the big end bearing/pin but the rod should not be blue. Perhaps the last top end never seated properly.

good deal..$1500 in wheels brakes and tires !

Id put a crank it it. At least a new rod on your crank at a minimum. That wrist pin got starved for oil at some point.

The bottom of the piston will usually look like that if its been run really hard and slightly lean on the main jet. Its not horrible though.

The cylinder looks fine. Hone it and go. It needs a piston though for sure.

Id second the suggestion with making sure the case seals are good and you don't have an oil migration problem that just scared the other guy off because he didn't know or understand what was happening. 200-250cc of oil out of the engine side sounds like a migration problem, because burning off 400cc's of oil is a smokey bunch of oil out of a single cylinder. The rear tire would be dirty and wet Id imagine.

Measure what you get out of the trans if you havent drained it yet.

Well thats all good to hear and yeah I really didnt think about the seal leaking thats a good point. Its getting a hotrods crank, wiseco piston, and all new bearings and seals. So it should be good to go afterwards anyways. Thanks for the input. Glad to hear they cylinder looks that good in your opinions. And as for hours id think its safe to say there were a minimum of 60 hours on it. I know it had 2 sprint races and practice time on it at Texas World and that straight is a killer...

Yep you guys were right, the crankrod is colored that way from the factory. Please excuse my lack of knowledge in this department

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