If you're doing a shaft delete, you're getting a set of digital scales and matching all the rod & piston assemblies and balancing the crank. There's a lot of talk about how detrimental is it to remove the balance shafts from an engine but there are plenty of engines around that don't have balance shafts in them and they don't massage your legs from vibration or fly apart. You'll need an M8 head for improved flow (or similar), derestriction of the intake side of the head, a good flowing exhaust system and headers, lightened flywheel, custom ground cam and anything other than the stock inlet manifold (it is GARBAGE for performance). I think an EDIS ignition system is a worthwhile upgrade. If you have the coin for DCOE Webers or Mikuni PHH side drafts, you have the coin to buy bike carbs and get a manifold made up (you'll get change in your pocket and the bike carbs run rings around DCOE's and PHH's for fuel economy and response)