Finally got my parts in for my 200x..........I am going to use full synthetic oil when I have it back together...Can I use a "natural" oil based assymbly lube when I go together, will they mix ok or not???????????? Thanks...

 

You'll be fine. No problem mixing dino and syn.

Personally I would not use syn right from the start, but thats just me.

 

exactly, synthetics tend to lube so well that "wearing" in the new parts on a rebuild such as rings doesn't give them a good chance to seat, you may want to do your break in time with good old petrol based and change to synthetic afterwards, I did a rebuild on a moto4 years ago and used synthetic while breaking in and could never get the rings to properly seat and the engine smoked, pulled it back apart, honed and installed new rings and used petrol oil after that and changed to synthetic and everything was fine.

 

ive read that once you run an engine on sythetic oil you shouldnt switch back.