Won't start
 

I have a 04 polaris scrambler 500. I got it out to ride the other day and it idled fine but when i went to go it sounded rough so i tried warming it up etc. It killed itself and would not start back up. I have spark, fuel, and fresh oil change. But it won't start. Not sure what the problem is. Any suggestions welcome.

Is the starter turning over? What happens when you try to start? Is fire a little bit? No noise at all? Starter whizzing?

Because it was running bad, and if the starter is turning over, I would wonder if a sensor. Not familar if they have crank posistion sensor or such. Something needs to tell it when it is time to spark.

When you say you got fuel, plugs are wet, or you simply have gas in tank? Cause it also sounds a but like fuel problem.

1. Fuel. 2. Air. 3. Spark. 4. Compression. If you have the right amount of them, there's not much left besides timing. But if the timing was off that much I don't think it would idle fine. I would check the air filter and duct, and go back to 1, 3, and 4, and see what kind of numbers you get.

It doesn't.

It turns over good. Thats why I first changed spark plug but didn't help any. Feels like some moisture on spark plug tip. When add a little throttle while trying to start, you can hear it 'pop' inside as it sounds like its trying and occasionally backfires if give to much gas.

I had that with a bike once, Was weird would start with stock igntion,but not after market. Some people though battery votlage cause 6 years old. Once I started it, I could put after market in. I replaced CPK, map and battery. That problem seemed to go away then mystery stalling when coasting. Replaced coil and that went away. That was around 30k miles ago. One problem with throwing parts at it, is you never know for sure. But it had 50k on it so new parts were maintence. I kinda think the stalling was coil. The failure to start dunno. Maybe old battery, but the replacement battery went another 7 years and never happened, few more years and still not happening. So maybe sensor.

So dunno.

"I got it out to ride the other day and it idled fine."

Take the air filter out and spray some carb cleaner in the intake tube and see if it fires up briefly on that. If it does fire up shortly, drain the carb bowl and see if it looks like water in the fuel system. When you say you have fuel, did you pull a fuel line and verify its flowing through the fuel lines, or did you just fill the tank with fresh fuel?

everything was running, before it died.

And how did the timing suddenly get so far off that it killed the engine? I'm sure Tkoes would like to know and so would I.