I'm working on a friends sp500 ( I think it's about a 98) and the thing runs fine but as soon as you give it a little throttle it spuders, coughs farts and dies. Is this a common problem?? He said his dealer checked the carb and all was fine but who knows. Please help!

 

if the machine is doing exactly as u described, it has got to be an air/gas restriction
somewhere.. my guess is the carburetor.. can't imagine the dealer saying it was fine
if it does as u described...the carburetor may need to be taken apart and cleaned
especially if it sat up and bad gas got into it..

for an engine to do as u described, it has to have an air/gas restriction somewhere(lines,
carburetor,exhaust, etc..). and this is not normal.....sounds like time to go find another
dealer.. for every good dealer you'll find 2 bad ones...not tryng to be cynical, just my
experience with polaris dealers.

 

Check the ETC. (electronic throttle control) If the throttle isn't adjusted properly, it will do the exact same thing you are describing.

 

Sounds like the pilot jet is stopped up.

 

I recently had these symptoms on a friend's 500HO and it turned out to be a loose clamp on the boot between the carb and the engine that was sucking in too much air at load. Also, make sure you have fresh gas and not some that has been sitting around for months. That caused another similar situation for me.

 

Thanks for the help, I was wondering if you can disconect the throttle saftey switch or bypass it some way. I also heard that the cams were famous for wearing off of the 500s is this true also wondering what the valve clearances are. Once again thanks for your help.

 

Both valves set at .006