Man I haven't been on here in a while

Anyways, i have had my 2004 500 for about 5 months now with no problems. always ran great! well i rode it all day yesterday with no problems, put it up and went get it one today cranked and idles fine but when i give it gas and cuts out at 2500 and if i hold the thottle down it will die. it just done this all the sudden with no warning signs.

So I changed the plug and the old one was blacker than the ace of spades, so I ran the new one and pulled it and the tip was white?

I also found out with the breather lid off and if I slowly push the throttle it will rev to 6k But if I push it quickly it will bog down around 2 to 3k. And eventually rev up.

Again as soon as I put the lid back on it bogs no matter what and if I hold it, it will die.

Hope this will give you guys some ideas

 

Might be time to replace the carb needle and seat could be running rich,is the air filter and pre filter clean? Plus most times you have to have the air box lid on to run right(too lean) Plus check plug wire as this was a problem in 04 about being pinched under the tank.Plus not a bad idea to check valve clearance (.006 intake and exhaust)Also 2004 model Sportsman 500s were included on the expanded recall list on ecm module replacements. If you still have the black Chinese module, have it replaced,can cause all kinds of problems. OPT

 

Seems like I heard about the wire problem and module recall on the 04s but where's it at, I haven't seen it.

Would the replaced one be a different color than black?

I havent had time yet to pull the carb yet but I did check the diaphram and it looked good

It's just hard to believe it being something big just sitting over night

 

The module is under the front panel.They can go out at any time!! If its BLACK,have it replaced! This is Chinese and the replacement is silver and larger and made in the U.S.Plus I've had the replacement ecms go out also(several forum members have multiple replacements!) Plug wire problems would usually show up on the atvs after about a month or so after being sold,at least the ones I had to replace were!
They would pinch under the tank from vibration and usually just quit firing period! I just used 7mm plug wire instead of sending in the coils as the bulletin wanted you to do! OPT

 

it seems to be fireing good and blue spark. But I haven't checked for it a pinch yet.

 

Just out of curiousity I ran it without the filter and put the lid back on and ran a lot better without the filter but still didn't quit have the power it had before.

I checked the oil and seemed like it had a small gas sent and looked rather thin, so I checked the clearance on the rockers and it all seemed fine just needs some adjusting and change the oil and I guess rebuild the carb.

Also as far as I could tell it still has the Chinese module by the radiator

 

Replace the needle and seat if gas has contaminated oil! Also have the ecm replaced! WILL go out sooner or later and can in extreme cases cause burnt harnesses or fires! Its under WARRANTY! OPT

 

Will do. And I'm sure it is the one that says made in China that's by the rad cap?

 

Sounds like you just have the regulator/rectifier if the module is close to the radiator! NOT ALL 2004 Sportsman 500s had the ecm module (located under the headlight area!) If you have the hub activated awd system,then you don't have to worry. Only the 2004 Sportsman 500s with centralized awd systems had the ecm modules! SORRY about that,just assumed you had the centralized awd! Just check out the carb! OPT

 

What's the difference. It has selectable 4wd.