I'd try running it with out the spark arrestor and see what happens but it sounds like you may possibly have another flooding type problem.Is your manual choke turned on by any chance?...You could also try turning off the gas and see how the engine responds.......If it runs better breifly you probably need to clean out the carb...When our 90 sits for a long long time(more than a month) it seems to load up with oil..I get on it and wind it out and it clears itself and then its fine.It smokes like crazy during this time.

 

it was the spark arrestor... cleaned it out and she runs like a top.

funny story when i was messing with it i turned the idel screw on the bottom of the carb all the way in to
try and get some power out of it well when i fired it up the dang thing ran me in to my sportsman i got a nice bruise on each leg...lol...
thanks for all the help guys..

 

I don't know if it's all kids quads or just my kids Etons, but I have had to completely clean their carbs now 2 times each and they are less than 8 months old. My kids ride in the mud, rain and sand, (we live in Oregon). Each time they would start fine but the second you started to push the gas they would die. Each time I cleaned the carb out I found junk in the bottom of the bowl. After removing they run like champs. I can now strip it down in about 30-40 min. Easy after you do it once. I also farted witht he spark arrestors and eventually tool boxed them as they do restrict power. Only put them in where fire season warrants it. The CDI would not suddenly change the power, but if it is idled down on you, you're definately not getting the power the quad is capable of. Over all I am pleased with the quads for easy to ride kid starters.

 

Try a 20mm Keihin properly jetted and a decent fuel filter. All your problems will go away.