I have a 505 ktm carbed with electric start only and at first I had issues starting it but I have made a couple changes to both my technique and my bike and it will start in any temp now. First because of the fact that I only have electric start I had to install a much larger battery in order to be reliable. Second normally in the summer I never touch the throttle before cranking but in the winter I give it six or so twists before cranking if it doesn't start six more today it was minus twenty five degrees C and it stated just fine with this method.
I ride a YZ450F -05 right now and have to kickstart it. Works great at least to down to -15 where I have tried it so far. Will buy a wr450f instead though, since I want electric start, lights and most of all a really low 1st gear.