Oil leaking from exhaust

Either something is wrong with the new bottom end, or problem with the assembly of the cylinder to it.
Was xyl and head retorqued after hear cycles? Engine leak tested after assembly?

All suggestions thus far are pretty much spot on. Arguing about whether or not to do them will get you less further help.
It's all a process of diagnostic elimination. As are asking questions about your set up, and what you have or haven't done or tested.


Are ALL electrical components the ones from the engine that did run?
Yes all of them are. And I couldn't do a heat cycle because it runs so bad
 
So it won't even run/idle for 5-10 minutes?
A heat cycle is warming engine to operating temp, then let completely cool. Doing this three times allows expansion/contraction of parts, and retorqueing head and cylinder nuts to be sure they're still tight.
 
So it won't even run/idle for 5-10 minutes?
A heat cycle is warming engine to operating temp, then let completely cool. Doing this three times allows expansion/contraction of parts, and retorqueing head and cylinder nuts to be sure they're still tight.
No it'll idle but it heats up in about 1 minute to running temp
 
:eek: whoa, uber lean !! Mine takes about 5 min before I can't hold my hand on cylinder.
Or you have extremely excessive friction, like from a bent or twisted rod, or something.