Stainless exhaust valve regrind

[richw]

I am freshening up my 84 bmw r80 st airhead and thanks to my brother i have to send one side out to have the exhaust rethreaded.

So the compression is down 12 psi and when I did the solvent trick there was noticable leakage of the exhaust valve.

Pulled them and guides are weak and the valve and seat are pounded into an s curve. So I look in the afterbirth manual and it says that the

Stainless valves can't be re ground.

Plus they say the seats were not hardend for unleaded. 1984 weird

stock valve, guide, seat parts alone 120 (after market 75) per head

If I had the bmw machine shop do it I'ld be at like $500

Does anyone know if this is BS or not this is like the spare bike for doing 2000 miles a year.

If I wasn't informed I probably just resurface the old for near free


[COLOR=orangered]

[Karaya One]

The seats were the weak spot for many of those Boxers. A good way to tell was the valve clearence not keeping, and them constantly measuring tight.

If you are replacing the seats, do the guides. Luckily, you only have two two-valve heads to pay for.

And you can regrind stainless steel valves. Vance and Hines did it for me when I built my first Superbike engine.

The valve seats are the only major weak spot for that engine. Otherwise, it is a rock solid powerplant that will last several hundred thousand miles.