I have been working on a 2001 polaris sportsman 500. The problem I'm having is it idles just fine when you give it gas it will back fire through intake and exhaust. I have installed new battery. Removed and cleaned gas tank. Taken carburetor apart and checked and cleaned it. Was pretty clean already. Installed new plug.

 

Have been told by several that camshaft was bad about going out. Removed valve cover checked cam no scaring on cam checked valve adjustment is in spec. Checked timing is in time. Removed flywheel cover checked key all is in place. No matter what I've done does not help or change anything about way it runs. Please please if someone can help.

 

Camshafts usually weren't a problem on the HO models. Cleaning a carb doesn't always work. If you take one off install a good carb kit and blow all passage ways clean. Then at least you can eliminate the carb as a problem. Plus pull the fuel line and crank the engine over.Should be a steady stream of fuel if the pump is ok.Shindy Carburetor Carb Repair Kit for Polaris 2001-02 Sportsman 500 4x4 03-408 | eBay Plus this is a hard carb to set the float right. Look at this post on the BST40 carb.Shows how to set it correctly.The BST-40 Bible | Adventure Rider If you still have problems after this,get the cheap manual and go through the trouble shooting sections on fuel and also electrical. 2001 Polaris Sportsman 500 HO Service Manual PDF Download

 

Is it a possibility that the rev limiter may be affecting the running of this thing

 

Possible as the limiter is in the speedo itself on this model,not a separate module like the older models.That's where the manual would come into play that I listed. I'd still check the fuel pump and eliminate the carb as a problem,then move on to the trouble shooting guides in the manual if need be.

 

So I got everything cleaned put all back together. Is running same way. Unplugged black wire on front or a tv coming out of black box. It runs great. But cannot shut it down. Where is rev limiter located. And where best place to get one. Owner wants replaced not by passed. Thanks for all the help. It is appreciated

 

The limiter is built into the speedo not a separate module like used on older models.I don't know of any way to bypass it,only to replace it IF you narrow down the problem to it.You unplugged the black kill wire from the cdi that's why you can't kill it. If it's running better with the wire unplugged,then possible the problem is within the cdi module itself or could be an ignition switch,left control switch or their wiring.These switches tie into the cdi kill wire.

 

I can use the reverse override button. It will also allow me to rev up the engine

 

This you can try as some others have done and see if it helps: Pre 2003 and almost all models that do NOT have the combined override/speedo function button.
Trace wires from the override button (gray/white & gray/orange) Cut the gray/orange and tape up both ends. Cut the gray/white and tape up the end which goes to the override button. Connect the other end of the gray/white to the red/white (ignition supplied 12v) You will also need to trace the purple wire which comes from the handlebars and simply cut and tape both ends. This just bypasses the reverse over ride button.

 

Do you know where good place to get needed part to fix this atv.and is it the Speedo that I'm needing