RH has the benefit of knowing the history, maintenance and condition of his engine just before the Big Bang. All other engines are a guess, unless he knows the person that created the donor engine and the exact circumstances around the accident. Any replacement engine should have a leak-down test if at all possible, this test is far better than a compression test.
A Gen II can most likely be substituted but there are some considerations which were discussed in another thread.
In a perfect world, RH would pull his crank so he can inspect the crank plane bearings, rod bearings, rods and wrist pins for damage. Based on a large sample group of one, my engine, it would most likely be a good gamble that the reciprocating assembly is undamaged. In my case I had stuck rings on three of four pistons. Most likely nothing to do with the cam catastrophe but there was never going to be a better time to fix the problem with a new ring set.
If RH got his cylinder head off without fubaring it when removing the head bolts it should be ok to reuse. For the cost vs return, I would recommend having new valve guides installed. The valve seats need to be carefully inspected and possibly cleaned up with a little machining. With some careful work using a flat plate, V Blocks and a dial indicator the cams can be checked for shaft trueness, journal damage and lobe damage. I suspect that the cams can be reused. If the cams are replaced the cam caps should be replaced too.
I would recommend new buckets, valve springs and keepers to go along with the new valve set. The FSM says if you replace the cam chain it should be done as a set including the cam shaft sprockets.
All the little bits and pieces like the head gasket, side cover gaskets, o-rings, shims, keepers add up. The big ticket items are the cams, the cylinder head ($1.2k) and valves.
I have almost all the parts that RH needs, with the exception of a valve still stuck in the damaged cylinder head and one broken valve. I also have a full ring set, less one broken compression ring that was welded onto the piston. I will be willing to donate all these parts to his engine rebuild B) That's what friends are for!
I don't know what your time line on this is but I just found out I am buying my bike back for $900. I have no idea what kind of shape it's really in, I do know the oil pan was damaged and it was leaking oil. The built in kill switch should have killed the motor before the puncture occurred so the motor should be fine.
