My 2001 Scrambler 500 2x4 is running very rough and backfiring only while in reverse. It otherwise runs perfectly. Also, it seems the bypass reverse button isn't working (not sure--just got this thing and am unfamiliar with it) and thought this might be a related issue.

Thanks!!!

 

Sounds like the overide is not working. Check the wires and switch. I think there is a bypass trick to avoid the over ride all together.

 

Just pull the black wire from the reverse limiter module under the front panel to defeat it. You'll have full power in reverse without having to push the yellow over ride button. These modules all fail sooner or later.Some limit in reverse even while pushing the over ride button,some die when you place gearshift in reverse,and some start limiting in forward gear. Just a bad safety feature by Polaris that doesn't hold up. Module #30. Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse
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Thanks to you both! Yeah, I'll be doing the bypass thing...sounds like the way to go.

Anyway, very much appreciated!

 

Worked like a charm! And thanks for the link to the diagram--really helped. Nice when something is an easy fix!

 

After doing all maintenace in the fall (oil change, grease, air filter, battery charge) the machine was parked and all seemed well. I only use premium non ethanal fuel with stabil which lasts for years. Pulled it out just now and it stumbles/runs rough exactly like the reverse limiter does when you don't hold the button in reverse. Sounded electrical so we changed the plug- same thing. Your site was very helpful in trying to figure out if maybe the reverse limiter wires were shorted but all looked OK. My freind told me a story about a motorcycle trip that a rider opened a pack of cigarettes and the cellophane wrapper sucked into the carb and caused similar symptoms. I said NO WAY and pulled out my brand new air filter. Turns out that when I installed it the foam in front of the intake had fallen down and got sucked in. 2 hours online- I am a certified auto tech for 45 years-- don't forget the basics!!