Kevin's 1980 XS650-G "Restoration" Thread

Btw.... wanna easy way to de-carbon the combustion chambers?
Wire wheels. Get various sizes.
Took about 30sec to de-carbon this combustion chamber.

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Several applications of paint stripper will do the trick. I also use it on the combustion chambers and exhaust ports, and to remove the old gaskets. Here's some pistons after the 1st application ......

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...... than after the 2nd ......

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I then finish the clean-up with chrome polish and the little wire wheels in a Dremel ......

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Still working on cleaning stuff up while waiting for parts..

One thing I’ve done is deburr the groove in the head gasket mating area, I really didn’t like how ugly it looked, also did the outer edge and inside cam chain journal edge. Has anyone else addressed this? Or is it just my OCD?
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Weight reduction? +5HP?? Or head gasket leaks.. 😬🤞
 
And inspecting my valves I notice some decent pitting at the ends of my intake valves, exhaust have no pitting and look good. Lash adjustment screws have a little wear also.

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Can the valve ends be serviced by grinded down to a clean face or is that too much? I have access to a nice tool grinder at work. And that adjustment screw is the worst one, the others show less wear. Should I consider replacing ?
 
New valves it is..

I’m looking at 2 NOS valves for $70 on eBay, or should I just get some new ones from 650 Central?

Here’s some pictures of the rest of the valves for reference..
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Also question about new valves, will I be okay just lapping them into the original seats or do the seats need to be recut?
 
I’m looking at 2 NOS valves for $70 on eBay, or should I just get some new ones from 650 Central?
2 NEW intakes from 650 central are $70.... same price. Get the new ones if you can.

No need to recut seats unless they're damaged or you replace the guides.

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Yes, the elephant foot adjuster screws, I was going to mention them to you. I put them in all my rebuilds. They address the issue of the worn stock adjuster screw and stop further wear on the valve stem tops. They require a bit of grinding on the rocker for assembly/disassembly clearance so can only be installed when the topend is apart. I used to grind off the whole bottom of the rocker but now I just bevel the screw hole with a tapered stone in a die grinder .....

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You need to grind enough off so the beveled portion of the "foot" will retract into the rocker. This is required for assembly/disassembly, so the screws can be backed off enough so that they're not touching any of the rockers ......

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The "foot" covers the entire top of the valve stem so wear from that one little point on the original screw is eliminated. Also, the "cup" where the "foot" attaches to the screw fills with oil in use and this acts sort of like a hydraulic adjuster. They run quieter and can be run with larger clearances as well (to a point - get too big and they'll make noise too).

The way I used to do it required removing the rocker arms. This new way doesn't, they can be ground in place.
 
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