Interesting thing I've noticed with my Deuce - I haven't had it very long, so I haven't had to try any real cold weather starts. But - it used to be pretty touchy to start, even in relatively warm "short sleeve shirt" weather. It does have the ether start system but the ether cannister is empty so I haven't tried using that either. SOP USED to be pull out the hand throttle 5 clicks, floor the accelerator pedal and crank. It started like the old Pratt-Whitney radial aircraft engines - First one cylinder would fire, then another, and so on until all six were firing. Then I'd have to play with the accelerator 5-10 seconds to keep it running between 800-1000 rpm until it finally settled down and started running smoothly. If I let off on the accelerator too soon it would die on me. Once I got it running OK with my foot off the accelerator, I still had to keep the hand throttle pulled out for 30-60 seconds or it would die again. after a minute or so, I could let off on the hand throttle and it would run OK.
A short while ago, I decide to turn up my fuel delivery adjustment, as the power seemed a little off and I just like to f**k with things in general. Only turned it up one flat on the nut, 1/6 turn, since I don't have a pyrometer yet (working on that) and didn't want to melt any engine parts. Noticed a significant increase in power - better throttle response, held speeds on steep hills much better. But I was amazed at the improvement in starting. Still floor the accelerator pedal and crank, but it fires off right away. Still have to play with the throttle a couple of seconds to keep it running between 800-1000 rpm until it settles down, but then I can take my foot off the accelerator and it will run smooth and steady at 800 rpm, no hand throttle needed. Can't wait to get my pyrometer installed, I bet another 1/6 turn on the fuel adjustment and it will start and run smoothly with no help at all from the accelerator pedal!
My best guess on this phenomenum - while the fuel delivery adjustment obviously sets the MAXIMUM fuel delivery rate, it also sets a MINIMUM fuel delivery rate, independent of the idle speed adjustment, untill the engine is up to speed and the fuel governor is able to take over control of the fuel delivery.