Didn't you have to rejet your carb? Where did your get the jets and how much? What size?

I am going to have to rejet also with the snorkle an muffler mod. Mine backfires real loud when you open it up and let off the gas.

 

Lots of jets here if you want to look... www.kimpex.com (whilst you wait for max)

 

i did rejet i went from a 148 main to a 155 and a 90 piolt jet to a 95. well i ended up going back to stock jets because it would bog when i got in bad mud. i know all i have to do is start working my way down in jets but my plug looks good and there is nothing wrong with the backfireing i just hate to here it do that. i would go wit a 152 main or a 92.5 piolt. oh and there were not but like 4 or 5 bucks per jet and i got them from my local wheeler shop. i think he ordered them through parts unlimited