personally i would set the needle to centre setting then turn mixture screw right in so you have a starting point turn mixture screw 1 1/2 turns out and see how it runs that is a basic set up setting and a good base to work from as you can give it another half turn in or out easily to check how its running,and its normally for bikes to need choke to start in cooler/colder weather and the revs will always be higher due to the fact its getting less air /more fuel.running at high rpm and putting choke on will cause it to die as you are flooding the engine with to much fuel not enough air,the only time you wouldnt have the problem was if it was running to weak in the first place