Titanium valves

It's been about 15 years since I last rebuilt my 1948 u. And I'm intrigued by some of the new products are available now. I am currently running 13 in barrels with a hardened valve seats. Over the years of course I've only been able to buy steel valves, which even with lead additive in the gas the valves get beat up and lose compression. Now I've been online and found some titanium valves and some stainless steel valves for the big twin flatheads. Having 2 hardened surfaces sounds good to me. My question is has anybody run these titanium or stainless steel valves? How are they on the guides? And what kind of clearances are best for such valves. My old 1948 bike Melanie runs pretty hot sometimes because I am running a set of 4 5/8 inch Truitt and Osborne flywheels with high-performance corvair Pistons. I put a fair amount of miles on the old girl every year because it's my daily rider so anything I can do on this rebuild to keep her a bit more maintenance-free would be great.

Well I've had this post out there for a few days now and I had no feedback. Surely there somebody else out there that put serious miles on their Flathead that would be excited about not having to lap in the valves every winter.

1948u
There are several that put some real miles on their flatty on here. They are probably out riding instead of monitering the site. One will chime in shortly. I've only got just a little over 2000 miles since finishing my 1942 U 4 years ago so I don't qualify.
F

stainless steel is pretty much the standard for valve material. i think titanium would be too soft for a valve? if you are getting 15 years out of a rebuild why would you change anything? of course you could hard-face your valves with a nickel-chromium-boron alloy .

[Pa]

There are titanium alloys which are hard but it has been a long time since I worked with those materials to remember their names. Titanium is very light also. Another issue with titanium is it can burn if it gets hot enough. It burns like magnesesium. [ my spelling sucks ]. Hot as the sun one might describe it when it burns. I once witnessed a dude polishing a titanium wrapped industrial roll drum when his polisher ran out of coolant. He was not paying attention to the loss of coolant and the drum set a blaze. The giant lathe it was in and the very high priced roll drum disinegrated when the titanium had finally burned itself out. Nothing puts out that type of fire but the fire running out of the fuel.