Can this crankcase cover be saved?

I'm a dumb ass and made a VERY big oops when repairing my YZ400F. For those who have been there and done that, can I have this case repaired by a professional? I'm not sure what it is made out of, my guess would be magnesium. If you look toward the bottom right you can see the chunk that is missing. It's on the rag (which so happens to be one of my ex's shirts :p) in the picture.

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Edited by dirtynasty

How did that happen?

I would not attempt to have that repaired. Head over to ebay...

Poor install. I didn't have it sitting flush in one spot and when I went to tighten the bolt down it snapped. I was praying like hell that there was some chance I only broke the bolt in half, but NOPE!

Looks like eBay has them for okay prices. Hopefully the one I am eyeing is around in a week. I've only budgeted for my street toy this week. The YZF will have to wait. :( &%$#@! and I really wanted to ride next weekend too. Well, I know better now.

if its aluminum you could try to repair it but i would think that for what its going to cost to repair you could proably get one of ebay. but thats a big chunk missing, you can take it to a welder and see what they say.

jbweld or take it to a welder if your keeping the bike

Not really sure why this thread got moved. I understand it's specific to a bike, but the main point was cover repair. I figured more people experienced with fixing metal pieces would view the general forum than the YZ400F forum. Hell, if I didn't mention what bike it was for then this probably still would be in the general forum. Could a mod move my thread back please? Thanks.

Edited by dirtynasty

JB Weld will work. It won't be real pretty, but it won't cost you much and you can be riding tomorrow.

I guess it's worth a shot with the JB weld...I mean the cover is already FUBAR otherwise. I suppose the worst thing that will happen is it will blow apart when I'm riding and piss oil everywhere and I'll have to push it back to my truck. I still plan on ordering a new part. If anyone has any better ideas for a permanent fix (i.e. welding) I'm open to it!

jbweld will hold as long as it's not a load bearing part of the case

It's an attachment point that broke off. I can only assume the only loads that bears is that of the other attachment points.

Edited by dirtynasty

Use it as a bookend get arounther one.

If you have the part that broke off, it can be welded back on. However, that by itself isn't the whole job, since the gasket surface would then need to be milled back flat to match the rest of the cover. If you have access to the machinery, and time is a real big deal, then you might pursue that approach, but it won't be anywhere near as cheap as replacing it with used stuff.

If you're going to use JB or something, you'll need to be certain that the piece sits in place squarely so that it seals to the crankcase and doesn't try to pull the piece off when you bolt it down. Ideally, you would bolt it in place while the adhesive was still in a flexible state so it will be squared up when it sets. Obviously, this may not be the easiest thing to do.

I figured more people experienced with fixing metal pieces would view the general forum than the YZ400F forum.

You only need the right answer once.

If you have the part that broke off, it can be welded back on. However, that by itself isn't the whole job, since the gasket surface would then need to be milled back flat to match the rest of the cover. If you have access to the machinery, and time is a real big deal, then you might pursue that approach, but it won't be anywhere near as cheap as replacing it with used stuff.

If you're going to use JB or something, you'll need to be certain that the piece sits in place squarely so that it seals to the crankcase and doesn't try to pull the piece off when you bolt it down. Ideally, you would bolt it in place while the adhesive was still in a flexible state so it will be squared up when it sets. Obviously, this may not be the easiest thing to do.

You only need the right answer once.

Thanks! Really good advice here! I'll be ordering a used part off of eBay and I can only pray that I don't get a warped/broken one I suppose. $300+ is a bit steep for a brand new one for my present budget.

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