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Now what? Cylinder head journal and cam shaft worn

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I just bought a 1982 XL500R to restore (famous first words). I've got it all in pieces now, top end apart, and I found an unexpected issue (famous last words).

The camshaft is significantly worn down and there is a bunch of metal buildup on the cylinder head journals where the end of the camshaft sits. Am I SOL or is this something a machine shop can fix? I fully expect to have to get a new camshaft, but the cylinder head/valves are a bit more expensive and harder to track down so I'm hoping its salvageable. It looks to mee like the metal has built on the journals up from the camshaft, not worn down the journals so I'm hoping that's a good thing. 

 

Thanks for the help!

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It's junk.  Better to replace the rurnt parts.  Don't think a machine shop is your answer unless you want to spend more money and fix it twice.

'Rurnt' is a Southern word for ruined.  

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Dis-agree, sorry Jimmy.

  That journal isn't usually the one that wears out, and is the easiest to have machined,, either built up and re-finished, or a roller bearing fitted instead.

      Meybe heads are easier to find in the US, here they're rockin horse poo and get rebuilt easily.

 

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On 4/29/2017 at 8:00 AM, Jimmy Pascol said:

It's junk.  Better to replace the rurnt parts.  Don't think a machine shop is your answer unless you want to spend more money and fix it twice.

'Rurnt' is a Southern word for ruined.  

 

 

17 hours ago, Muzz67 said:

Dis-agree, sorry Jimmy.

  That journal isn't usually the one that wears out, and is the easiest to have machined,, either built up and re-finished, or a roller bearing fitted instead.

      Meybe heads are easier to find in the US, here they're rockin horse poo and get rebuilt easily.

 

 

I can find a used one of these for around $200 USD which doesn't seem too crazy. 

Muzz67- I'll have to look around to see what I can get this repaired for. What is the correct term for that? Seems like I've seen line boring thrown around in this context. Just don't want to sound like an idiot when I call around. 

Thanks guys. 

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Line boring just means that all those other bores associated with that journal must be bored concentric with each other in order to function properly, meaning all on the same centerline. Any misalignment means no oil film, but instead metal to metal contact and seizure.  Muzz67 has the 2 most feasible repairs, but you're probably in the $200+ range unless you can find an experienced neighborhood welder/machinist that wants a project to mess with. 

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On 4/28/2017 at 4:48 PM, bofar said:

I just bought a 1982 XL500R to restore (famous first words). I've got it all in pieces now, top end apart, and I found an unexpected issue (famous last words).

The camshaft is significantly worn down and there is a bunch of metal buildup on the cylinder head journals where the end of the camshaft sits. Am I SOL or is this something a machine shop can fix? I fully expect to have to get a new camshaft, but the cylinder head/valves are a bit more expensive and harder to track down so I'm hoping its salvageable. It looks to mee like the metal has built on the journals up from the camshaft, not worn down the journals so I'm hoping that's a good thing. 

 

Thanks for the help!

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That is really common.  best fix forever is go to megacycle.com and get one of their needle bearing cams and have your head machined by them to fit it.   By the springs for the cam you get and go faster and know that your cam won't do that to the head anymore.  You can make that engine bigger,  but unless you are going to have some serious head work,  the right cam, a wiseco 12-1 piston as close to stock size as you can get it will make it as fast as the cranks shaft is good for.  Very strange crankshaft.  

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I'd already have bought parts off Ebay, installed them and been riding by now while you guys are still talking to machine shops.   

Edited by Jimmy Pascol

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Engine Dynamics co. EDco has fixed lots of these with a roller bearing set up and Mega Cycle also sells the bearing setup.  If you're racing it that's how I would go. If it's a trail bike find some E-Bay parts and carry on. Don't forget to change the oil more often.  The 500 Yamahas don't have this problem they have roller bearings from the factory :)    Just saying'

http://www.enginedynamics.com

 

http://www.megacyclecams.com/catalog/catalog_optimized.pdf

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