Question BLUF: how do I know if something is wrong without a known-good reference engine or cringing while on a post-breakin test ride? The Background A few years ago I began the process of rebuilding my 750 SECA (1981), starting with the engine. I am a total novice and this was my first engine rebuild ever, but since I bought a second much newer bike I figured why not. Fast forward to today and things are finally running well enough to ride. Except now I have no idea if everything is good enough. I will list some minor issues below but the real concern I have is that I'm not actually sure if I succeeded. I'm treating it gently until I hit an arbitrary 100 mile breakin duration. But it's been so long since I've ridden it that I can't even remember how it ran before (and it wasn't in great shape before anyways). So here's where I decided to call for help. The Question What do I need to do in order to verify the thing won't go kaboom between my legs? What sort of tests should I be doing? What should it sound and feel like? The Symptoms Strong(?) Vibration (no idea how much is normal and at what RPMs) Harsh Sound in the mid-RPMs? (I forgot how much anxiety those cams used to give me) Slow to drop revs (I suspect carb adjustment issues) Highly sensitive to choke adjustment until fully warmed up (probably the carbs again) Had to increase idle to closer to 1,500 for a stable idle Some other (possibly) important things about the bike: Deck was professionally surfaced, so compression might be ever so slightly higher Cylinder sleeves and pistons are in spec (verified by the same shop that surfaced the deck) Leak down test looked good Compression seemed low, so I'm wondering if I did that test wrong Coils have been replaced Timing advance check with a cheap timing strobe didn't seem to match the specs in the manual Exhaust is in terrible shape and likely leaky at the crossover. I can't get the exhaust test port screws loose.