I have a brand new coolster 110 and I cannot seem to get the idle right. It shuts off almost everytime I give it throttle and then let off the gas. I can turn the idle screw almost a full turn and get it to idle correctly but then it seems to idle high after a little while. So I'm constantly adjusting it.

Also this thing vibrates pretty bad during certain rpm ranges. Is that just the nature of the beast or is it possible I have a bad carb or out of adjustment carb?

 

even though it is new, as your posts indicates, you probably got some solids and debris from the fuel tank down to the carb/jets. go ahead and pull the carb, disassemble it and clean the jets. this is a good starting point. while the carb is out, flush the fuel tank, make sure your inline fuel filter is clean, and then we'll go from there. make sure you pull the jets out and clean them. that is critical. don't know if you've done this or not, but here's a generic video that shows you. your carb may not be identical, but the principle is the same.

how to clean a carb on a ATV - YouTube

How to clean a carburetor in 15 minutes - YouTube

 

Thank you so much, I think that fixed it. It still dies when I first start it but as soon as it warms up it runs great. Still vibrates too, but I think it's normal.

 

so on a cold start, she'll start up but dies and won't idle? hmmm...what's your idle screw set at and is your choke assembly working?

 

I will get the exact spot the idle screw is past stock, but I rarely use the choke at all, should I give it a little on initial startup. I just usually just give it a little gas it fires right up. But will die if I let it go back to idle.

 

if not choking the quad works for you, then go for it! glad to hear you're all fixed up for now. have fun!