Good info, Jack. I'm really surprised that hydraulic valve lash adjusters have not become common on the V-twins. Motorcycle manufacturers avoided them in the past because the hydraulic units couldn't handle the high rpms required to develop max horsepower in the old inline 4 UJMs. They couldn't compress and decompress fast enough and caused a syndrome called "valve float" at higher rpms. With the advent of the V-twins, that don't operate at high rpm anyway, why not do away with the solid units and go hydraulic?
I love 'em on my Nighthawk. It redlines at 8,700, but the same engine with solid lifters can make about 10 more hp at 10,500. I'll take the hydraulics. If I never have to shim the valves on a motorcycle engine it'll be too soon.