??? sorry to hear. this is one of those "could be anything" problems. i guess the first thing i'd check are the vacuum lines and the fuel lines. they seem to be everywhere under the tanks of carb'd monsters. easy to leave a vaccum line unplugged or pinched. also easy to pinch a fuel line.
otherwise, sounds like fouled plugs. i really like NGK plugs...
I doubt this is the problem though, or I'd expect to have the same problems starting the bike after I've ridden it to work, which I don't.
The only thing I can think of is that there may be a problem with the choke (which looks like it's working OK (I can see that the choke slide is activated), an has a noticable effect on the engine cranking (it takes more effort from the starter motor to crank the engine over (more fuel being introduced into the cylinder?))) or the mix has been changed as part of the servicing, in which case the carbs may now be biased against cold-starting.
A buddy of mine had the same kind of symptoms on his KLR650 quite a while ago. Turned out that his valves had worn through the hardfacing, and weren't completely closed when the engine was stone cold. The cams were holding them open. But get it started and warmed up a little, the head grew enough that the valves seated and it started and ran fine.
Just thinking maybe they adjusted the valve clearances on your recent service, and got the openers too tight and the closers too loose.
you didn't say whether your bike is carbed or fuel injected. on carbed monsters, the "choke" lever is extra enrichment. on fi bikes, the "choke" lever is fast idle. i only completely "choke" when it's real cold, like near 0 c or less in hot weather, no "choke". every monster has it's own personality, especially when modified. try less "choke" especially if it's a carbie and even more so if it's been jetted.
Howie, fuel injection wasn't available on Monsters until 99 or 2000. You should have known that.
My 97 doesn't like starting when it's cold (less than 50 F) and has been sitting for a few days. It's obviously not as bad as your bike, but when cold like that, I'll crank for 5 seconds, then turn the key off and let it sit for about 20 seconds before trying again. In the worst circumstances, it might take 5 or 6 tries before it finally fires, then it will just barely run for a little while until if finally jumps up to 3000 rpms and I have to reduce the choke a bit. Nothing but full choke works for me to get it started initially.
It's my guess that a set of dynacoils would solve the problem. However, I'm too cheap to make that fix to my own bike.
initially i read the post before finishing my first cup of cofee. now i see it's identified in the beginning of the post. when my bike was new and not jetted, it would need some choke no matter how hot the weather, as well as a looong warm-up. after jetting, much less choke to start and minimum warm-up. i do get my full 6k between plug changes and good driveability, so i know it's not too rich.
the point i was trying to make is find the choke formula that works for your bike. i also missed the part about just in for service. Colin, unless you really don't trust the people who did your service, i would suggest bringing it back to them. since you were happy with the bike before the service, the problem most likely has to do with an adjustment they made, probably something minor like mixture screws. everbody messes up once in a while. i'd bring it back to them and leave it overnight so they can see what it does. as Don is, i'm baffled by a cranking speed difference with the choke on or off.
The change in cranking speed is due to the fact that with the throttle farther open (the choke opens the throttle slightly in addition to enrichening the mixture), more air is admitted into the cylinders before compression. Thus, more air has to be compressed, the starter motor has to work harder, cranking is slower. An easy way to demonstrate this is to do a compression check on an engine - once with the throttle shut, once with it wide open. Makes quite a difference.
Sorry about yur troubles :'( When I lived in the N.W. my 2001 carbd m600 would have trouble morning starting at around 30 degreesC too. I parked it out doors w/ cover as well. Then I began letting it set in a sunny spot for about 10 min and it would start right up with full choke. Maby try hair dryer for those really cold days? Did the bike ever have cold start troubles before the sevice?