Ok guys, Im a newbie to this but I inherited my grandfathers bike that is all original and is one owner(grandfather).  My dad has over the years tried to work and ride this bike but without questioning my father I have decided to start fresh.

Not sure of the year bike I have, I think it is an "M" model.  Serial Number M22118B  stamped below the crank cover.

Anyway:
i set new points at .013 gap. 
I have a J17L spark plug which is currently gapped at .020
I am getting good spark but I can't seem to fire off starter fluid or gas/oil mix, Compression is good what am I doing wrong

My questions are :
What is the correct spark plug number
with running only one plug what are your recommended gaps on both points and plug

I am using 6volt coil from dennis carpenter for WICO

Any help would be appreciated.

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