2008 YZ450f rod broke

Blew a hole in the right crankcase.. I think its fixxable,, bought the bike as is complete needing a cylinder, rod kit and this case fixxed for 1500..

Heres a few pics I got, advice?

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Edited by RobbieM16

replaceable yes

A good running 08 450 would go for the same price here. I'm pretty sure it JuSt needs to be replaced and could end up costing more to repair then to buy a bike that is good to go

Jeez, how did the previous owner manage to break the rod on it after only 20 hours?

$800 maybe. $1800 no. You have no idea what the rest of the motor looks like inside. It's likely that it dropped a valve first which took out the rod. You could be looking at an entire engine replacement. I wouldn't pay $1800 for that potential headache. JMO.

$800 maybe. $1800 no. You have no idea what the rest of the motor looks like inside. It's likely that it dropped a valve first which took out the rod. You could be looking at an entire engine replacement. I wouldn't pay $1800 for that potential headache. JMO.
I agree. It's a genuine can of worms. Even if the head is not involved at all, I guaranty there's more wrong with it than just a crank and a set of cases. I can see $1400 in parts already without considering any head damage.
Blew a hole in each crankcase,, near gasket surface. Is this weldable/fixxle, or replacable..

I'm buying this bike as is, blown up.. Guy wants 1800, bike is mint 20 hour bike, fmf exhaust. . I'm in Canada so yes, 1800 is quite a bit in the states, but a running 08 450 would go for around 3500 - 4500 here.

Either oil was never changed, or someone is riding all day long bouncing the rpm's off the rev limit.... YZ450 bottom ends are extremly durable.....

either way, get your wallet ready... it's gonna HURT !

I rebuilt a buddy's 250F engine complete new crank, head, cams, bearings and gaskets.... $2100 just in parts, not counting the 20 hours of labor I put into the job.

BTW, my buddies' crank initially siezed from the oil never being changed and took the whole rest of the engine along with it....

Edited by Polar_Bus

Don't get it unless it comes with a free spare engine! I bet the oil was never changed and he baked it.

It's not unreasonable to estimate $2000 in parts alone for that bike, I just rebuilt a buddy's '06 yz250f last year - new head, cylinder, top end, cam chain, etc. and the cost on parts for that was $1200 + and we ordered all of the parts out of the US. If we'd have ordered the parts up here it would have been over $2000.

So, if you pay the guy $1800 + an estimated $2000 you're at $3800. With that, you've got a bike that has a greater potential to cost you more $$ in the future. For that kind of money I'd buy an '08 that hasn't been blown up.

For $800 I might be willing to assume that risk, but I doubt the guy will sell it to you for that.

True, but at least with parts you can pay over time. If you only have 2000$ in your pocket and come come up with the rest a couple months down the road or more, it's a long term project that you can actually have now.

Sometimes I get into projects this way, don't have all the $ for something that is running, but have enough to buy a project and splurge on it over time.

If you do have the money for the parts and the bike all at once, then yea you'll want to just look for a running bike!

Well I took it off him today for 1500. The right case has a small, squarish hole near the top of the crankcase where the rod would stick out. Left crankcase is fine. The piece that broke off is inside the motor, which looks as if it can be welded. Head is fine, the cylinder was ruined however.

Worse comes to worse, crank kit with main bearings, seals and bottom end gaskets = 280$ shipped, Cylinder 240$ new, Crankcases 600$ shipped, both new, and stock oem top end kit about 140$. About $1260 in parts, and labour is done by a friend for next to nothing.

If this case ends up being welded, I've got a 08 yz450f for 2200ish with a brand new motor, I'm pretty happy with that considering most 08s go for 4g+ around here. (Reason I bought it as is)

Oh, and a valve wasn't dropped,, I think it was just something odd went wrong.. Possibly the oil,, not too sure the guy probably rode it like he rides his CR500..

Well I took it off him today for 1500. The right case has a small, squarish hole near the top of the crankcase where the rod would stick out. Left crankcase is fine. The piece that broke off is inside the motor, which looks as if it can be welded. Head is fine, the cylinder was ruined however.

Worse comes to worse, crank kit with main bearings, seals and bottom end gaskets = 280$ shipped, Cylinder 240$ new, Crankcases 600$ shipped, both new, and stock oem top end kit about 140$. About $1260 in parts, and labour is done by a friend for next to nothing.

If this case ends up being welded, I've got a 08 yz450f for 2200ish with a brand new motor, I'm pretty happy with that considering most 08s go for 4g+ around here. (Reason I bought it as is)

You make no mention of the head or cams, makes sure you have a GOOD inspection of the heads' cam journals. Most of the time with an engine failure the cam journals get trashed. Replacing the head is the component that sends repair parts costs through the roof.

If you do have to get any cyl-head work done send it to Engine Dynamics. They repaired my cam journals, replaced seals, and cleaned it to new for $350. Alot cheaper than new cyl-head.

I will be sure to check that out, thanks.

You make no mention of the head or cams, makes sure you have a GOOD inspection of the heads' cam journals.
Well I took it off him today for 1500. The right case has a small, squarish hole near the top of the crankcase where the rod would stick out. Left crankcase is fine. The piece that broke off is inside the motor, which looks as if it can be welded. Head is fine, the cylinder was ruined however.

Looks like the head may have been spared...

Looks like the head may have been spared...

What do you mean by it may have been spared?

I'm gonna try and get some pictures up of this case,, and if anybody knows what years are interchangeable with the 08 for the right crankcase let me know..

What do you mean by it may have been spared?

I'm gonna try and get some pictures up of this case,, and if anybody knows what years are interchangeable with the 08 for the right crankcase let me know..

That's English. He's telling the guy who thought you'd need a head after you already said it was OK that it's OK.

Crankcases are sold in pairs only because they are line bored bolted together as a set. You should not ever mix halves.

Alright, yea I've noticed that.. I called Engine Dynamics today and they said they'd probably be able to fix up the case,, so I guess I'll go that route. Ordering crank kit, cylinder and piston kit, and gasket set tomorrow. Splitting cases in the mean time to look for further dammage on cases

Does anybody know any other machine / welding shops in Canada that could fix my case to cut down shipping and what not?

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