all help appreciated: my sportsman has had this problem for the last two years. I put on maybe 20 hours a year, hauling wood, etc. Starts great, idles fine, it just doesn't have any power. I finally decided to do something about it when it quit, wouldn't start, discovered it was a bad stator-replaced, the first couple of times after that (maybe two quick runs) all kinds of power, spinning tires, etc. then back to low power. Replaced belt, air filter, and plug, no improvement. Checked timing, adjusted valves to .006, cam looked good, no improvement. Pulled carb, soaked overnight, cleaned, inspected, no improvement. Fuel filter looks ok, no spitting, sputtering, or backfires. Feels like carb, just stuck.

 

Sometimes just cleaning carbs may not solve problems. Install a carb kit and eliminate any carb problems or having to go back in several times as some have done. Plus check the slide vacuum,just lift up on the slide and see if it rapidly falls back down. Not unusual on an old carb to have a worn diaphragm or worn/sticking slides.Plus could be something simple such as the slide spring binding.Also you can pull the fuel line from the carb and crank the engine over. If the fuel pump is ok,should be a pulsing stream of fuel.f you eliminate the carb and fuel problems and it still doesn't run good,move onto other areas such as the clutches themselves.Again just replacing a belt may not help if guide buttons or ramp buttons are worn in the clutches. http://www.ebay.com/itm/CARBURETOR-CARB-REBUILD-KIT-POLARIS-SPORTSMAN-500-1996-Rebuilds-3130665-/331461107950?pt=Motors_ATV_Parts_Accessories&hash=item4d2c9f20ee&vxp=mtr

 

thanks for the rapid reply. Fuel supply had been one of the nagging issues, along with compression, clutching, electrical (grounding), and exhaust, I have yet to check. I will order the carb Kit today as a hedge. I was hoping for a smoking gun somewhere. I really appreciate the advice.

 

ill do the fuel check when I get back today. The slide didn't stick but it didn't slam down , more like elevator doors closing. Thanks again.

 

Yes it shouldn't slam down like a cable operated slide,but should have a smooth lowering of the slide with no sticking. Just one thing to check as the slide,diaphragm and plastic jet block assembly does take a lot of wear over the years. Dirt Cheap Yamaha & Polaris OEM Parts & Accessories – Cycle Parts Warehouse