occasionally when im riding my bigbear will pop...sounds like a gunshot...is this a problem that needs to be fixed?...or is the jetting just a little off...it usually happens when im going down a hill in 5th gear without the gas...right when i get to the bottom...thanks for your help...

 

my friends scrammy, when you give it gas, then let off completely does the exact same thing... BAM right, its loud as hell and cantbe good for the quad i suppose... good luck.

 

Jetting is off just a little, or the intake has a leak, or the exhaust has a leak.The popping is a symptom of a lean idle circuit.
If you dont have any leaks, turning the mixture screw out 1/4 turn, should stop the popping.

 

how should i check for leaks? and turning the screw out will richen the mixture right?...thanks...nothing is wrong besides that..its just really annoying

 

An exhaust leak will make some noise, usually sounds like a valve clacking. Look for carbon around the joints, which shows exhaust has been leaking. Try snugging up the intake bolts, and the clamp on the carb. If those look ok, then id turn out the mixture screw 1/4 turn.

 

do you know where the mixture screw is on a scrambler?

 

partsland
Looking at this picture, its number 32 for a 500 scrambler. Its on the bottom of the carb, in the recess, just forward of the float bowl.

 

It may be a bad cam, my friends big bear did the same thing and it kept getting worse till we replaced it and our sportsman did it to.