I have a 2002 Polaris Sportsman 500 HO that wont start and keeps backfiring while trying to start. Any suggestions, it only has about 75 total hours on it. (dont ride it much) I have tried a new plug and cleaned all the vent tubes on the carb!

 

Dump all the gas out of the tank , clean the carb and try new fresh gas. Also pull the dipstick and smell it to make sure you havent got gas in the crankcase. I have seen the needle and seat go bad in the carb cause people dont shut off the gas when their not running, fills the crank case with gas making it very rich, check it out and let me know.

 

when you pulled out the plug to replace it was it wet from a gas flooding?

 

I had starting problem with 02 500 magnum... backfiring out exhaust, fouled plug... found sheared flywheel key. Replaced all is well

 

no the plug was dry. cant figure it out, I guess Ill take it to the dealer. thanks for your help. Roy

 

This might sound dumb, But do you have alot of throttle play? If so, readjust your throttle cable so you have a little play. If you have alot of play, then It won't idle and it will backfire. Let us know if you have alot of throttle play so we can rule it out.

 

if the etc (electronic throttle control) is out of adjustment, it will not have fire. the thumb throttle sould have no more than 1/16th inch of play. you can adjust it easy. follow the cable from the handle bars (at the thumb throttle) and about 5 inches below that is a boot on the cable that you can seperate and adjust play.

 

I am curios to as this problem being solved, I too am having this problem on a bike I just bought 2002 500 ho RSE.

 

Let me throw this at you....
Remove the airbox cover...
remove the air filter...
use compressed air to shoot air through the carb. vent tube that is located to the left of the machine (light switch side) and runs through the frame rail under the seat.. the result should be the removal of bad fuel or settled water in the settlement bowl and it should also blow air to the airbox...
Clean airbox...
replace air filter...
replace airbox cover....

Choke and restart....

If this works you have saved yourself alot of trouble...

This also works great when you sink your carburated machine in a river....

Jon