So, I am building my RYCA and had a question that can likely be answered by a non-RYCA builder too.

I set up my manual decompression lever on my bike. I do not have a tank hooked up (so no gas) but I wanted to see if the motor turned over after all the messing around I did on the bike. A puff of smoke came out from what seemed like a couple inches to the left (as you are sitting on bike) of the header pipe as it exits the engine. Does this mean I don't have the decompression completely closed off? In other words, when the decompression solenoid (or manual lever) is activated, where does this actually create an opening in the engine? Is it to the left of the header pipe?

where is the exhaust valve that it opens?

Take off the front inspection cover.
operate your decompression lever.
nough said.