Valve Guide and Valve replacement

[BBS360]

Hey guys,
Through an unfortunate event (read: stupidity) I need to replace a valve guide. Just wanted to double-check before ordering parts.

-If I'm doing one it's probably best to do them all, eh?
-The combustion chamber is super dirty. Should I have a shop remove the old valve guides, clean the head myself, then bring it back to the shop to put the new ones in? Do shops typically do the whole process?
-Would it be best to get new valves too? I JUST cleaned all the old valves... not sure if they're in spec.
-If I keep the old valves I'd probably be good with a thorough lapping. If I get new valves get them cut?

-I saw xchris mention in another thread that the valve guides are still available from Yamaha. Ditto for valves?

Assuming I'd need these parts for my 82 XS400SJ?
4H7-11133-10-00 Valve Guide x4
93440-12052-00 Valve guide circlip x4
1L9-12111-03-00 Intake Valve x2
1L9-12121-02-00 Exhaust Valve x2
The # in the parts fiche for the valve guide appears to be a 1-oversize. Is this normal for a stock bike?

The price tag for this bike keeps going up.
Many thanks in advance...

 

[MrStubb]

Don't really want to pee in your beer but If I'm going thru taking it apart part any ways I'd go the whole 9 yards. Right down to checking the slugs & jugs. It's a tough pill to swallow but pistons & rings are really only 1 more gasket down. If nothing else you can make sure things are on good shape down there. Valve guides are usually a press fit so it would be a shop job. As far as replacing parts you'd have to get the specs & check the tolerances on your stems & guides. I don't suspect things are in real bad shape but do your home work these engines are close tolerance beasts. Good luck

 

[BBS360]

Don't really want to pee in your beer but If I'm going thru taking it apart part any ways I'd go the whole 9 yards. Right down to checking the slugs & jugs. It's a tough pill to swallow but pistons & rings are really only 1 more gasket down.

Those are the easy parts. Jugs have been apart for a while. Pistons and cylinders are all cleaned up. Rings are just a hair beyond end-gap spec. Cylinder cross-hatching is still slightly visible but I know someone with bore gauges so he's coming by tomorrow to check exact cylinder dimensions, ovality, etc.
Will be using the existing pistons and rings for now unless something else is crazily out of spec. Piston/ring/cylinder upgrades might be happening down the road so I'm not too concerned about them.

Valve stems appear to be within spec. Everything that has a specification that can be checked at home has been checked or will be soon.
It's the guides, since they really need a shop to do, and any wisdom about valves & guides that's not in the specs that I wanted to double-check on.

If I had to guess I'd think that it'd be a best practice to get new valves for new guides. I dunno.
The 1 oversize part # seems odd. Couldn't find anything that went into more detail on that.

 

[Wolfe_11B]

When I got my head done, i just printed out the specs from the book, handed the head to the shop and said have at it. Everything was in spec, but I had them do a serdi job on the valves for the heck of it (should be sealed up better than it was). I also had them deck the head a tiny bit to increase compression. So basically do as MrStubb suggests, just have the shop check it all. If it's a reputable place they will just measure and be honest with you if things need fixed.

You have to ask the specific shop about cleaning. All will clean stuff, but some have in-house equipment(cheaper) and some outsource(they will end up charging more). I was lucky enough to be working at an engineering company when I had mine apart, so I just borrowed the shop floor equipment after work for free

 

[drewpy]

I got my shop to put in new guides and measure up the vales to make sure they are ok.
the guides come as blanks and then they are reamed to the valves withthe necessay gaps (bigger gaps on exhaust)
my machinist was an ex bike racer so knew exactly what needed doing.

the latest materials are used too if you get new, you don't need yam specific valve guides