The tech at Eurosport has performed big bore kits on TBs and at least one update kit on early R3 that I know of. That's why I trust them. The shops here wouldn't admit they had heard of the update kit, etc. Someone else can better advise on all the maintenance. Or just consult the manual. I don't stress much over routine maintenance much. It is inadvisable but I don't check valve Clarence. None of my bikes has ever needed adjustment so I stopped checking decades ago. If I don't sense any issues I'll check the R3 at 40-60k or maybe never? I just replace worn parts, fluids and filters. But you're doing right to check out a newly acquired bike. Valkyrie, Magna, Rocket III. Can't believe we live so close ride/rode the same three bikes and haven't crossed paths
Do you still have the Magna?
Since I got the Rocket I'll have to start calling it Mighty Mouse.