My bikes and those of my mates (five in all) are set up on stock settings and start very well.
Points to note are:
They seem to require choke at anything less than hot. Stop for 5 minutes and you need choke again.
Use absolutely no throttle for hot and cold starting. Otherwise they flood and you have a big problem
with no crankcase drain plug.
If your mixture is out and you soot up plugs this will make for hard hot starting. Aim for that nice
tan colour on the electrodes. Keep a spare set of plugs under the seat if you are having starting problems
- it can often be a quick fix with a two stroke.
Look for carby leaks at the cylinder flange and the airbox rubbers.
That's all I can think of. In our case I have to say we needed to get the start procedure right (choke/no throttle) before
hot and cold starts were sorted.