bad midrange grurgle and backfires

[hankohlson]

so ive got a 2000 800 non ves in an iqr cahssis thats got a real bad stumble in the mid range. its ported with reeds, custom fit gen2 slp pipe with a stinger silencer. no lights but i put the arctic cat 200 watt voltage reg in it. I rebuilt the motor top and bottom. ran great for the first tank or so but then got this problem. it has good idle and once you get it wide open it rips. it barely runs and back fires in the mid though. not rideable. went up on the neeld and pilot and cleaned the carbs. ran better for a minute but then it was back.

could it be electrical ? tach works fine?

ideas?

thanks guys!

 

[keefer]

Sounds like you have some crap in the tank. Might want to drain and flush the tank. Could also try an inline fuel filter. Of course you will have to clean carbs again. Just a thought. Just went thru the same thing on a 1980's ss440.

 

[jager]

what elavation are you riding get the chart from slp put the jets they say to put in it.the slide needle is what you should make sure is correct because that is your mid range adjustment, had the same problem with 2001 800 backfire bad enough to blow the pipes off the can , on the chart you will see your jet size and next to that you see a #1 or ? that will be your needle position take top of carb off small allen bolt loosen enough to move keeper pull slide needle out adjust clip to the correct sitting worked for me hope it works for you .