OK gang, new to ATVs, brand new to forums so bear up with me please.

So we decided on ATV's on our family toys knowing full well that we would have to learn mechanic'n because there is no way we could afford to drag them to the dealership every time something broke. So, we bought this one knowing full well of the issue that I speak of with the assumption that it was a simple carb clean or rebuild. OOPS, what an idiot I was. I'm too embarrassed to say how many hours I have in this thing thus far but suffice it to say I'm at my wits end.

Through the help of the factory service manual and these forums previusly as a spectator only, this is where I stand:

2004 Polaris Magnum 330 4x4, apx 2000 miles.
Starts, idles, perfect (even when blipped or WOT is cut it drops back to perfect idle) but very boggy (not missing like rev limiter? IMO) under throttle from idle and or WOT.
Does not backfire or die unless you simply don't let off throttle at deep bog, but doesn't smoke. You can at times nurse it up to a fairly high rev but soon will begin to bog and not run smooth. This is not an intermittent issue, it happens consistently every time the machine is run, hot or cold.
Determined (IMO) a rich condition exists; removed air filter, condition improved, partially covered air intake and condition worsened, gas could be smelled coming through back side of carb...
Replaced spark plug (2x). It comes out black, somewhat sooty but not wet looking at all that I can tell.
Emptied tank, rinsed (with fresh gas), blew out with compressed air, filled with fresh 100% gas.
Cleaned air filter.
Replaced fuel filter.
Vacuum tested fuel pump and it bled down from 5" to 0 in 10-15 seconds so fuel pump was replaced and tested solid.
Vacuum tested needle and seat at fuel inlet fitting, solid.
Carb rebuild kit and cleaned (factory jets, settings, float height= .55 inches, level).
Tested with 120, 117.5, and 115 main jets, no difference, maybe worse.
Then went the other way (just to say I tried everything even though it ran counter to all the signs) and tried it with 125 and 127.5 jets and the boggy condition worsened. Finally just returned to factory 122.5 main jet.
Also tested various needle height settings, no improvement.
Each time I've removed carb for cleaning or adjustment I've re-clamped all lines and boots and tested both with and without air filter attached and condition absolutely worsens when air filter (K&N) is attached. I hooked up my shop vac to air filter and it pulled cleanly, no restriction.
Adjusted valves.
Removed muffler drain/cleanout bolt, no exhaust restriction but did discover a couple minor holes at rear of muffler.
Cleaned all ignition/electrical push plug/connectors with contact cleaner.
Checked all battery/other electrical lugs & connections for tightness, investigated for broken /damaged wires.
Battery tests 12.80V at idle, 14.30 at 1/2 throttle, 14.40 at WOT.
Compression test jumped to 90 PSI on 2nd or 3rd stroke, then to 160 PSI steady after 5-6 strokes.
Removed valve/head cover and checked every component for wear or damage, none present and camshaft mic'd out perfect.
I have not replaced any electrical or ignition parts, but battery faithfully spins the starter strong every time the ignition is engaged.

Sorry for marathon post but I just figured I'd include my entire journal in order to save a few Q&A volleys.

Really the only thing that I know left to do is to replace the coil, boot, and wire, then finally the ECM but I question whether that would help me out at all on a normally aspirated engine (Carburetor, no EFI)? Hate to spend the money on a no return part only to find out my condition still exists ...
I am COMPLETELY demoralized- any ideas?

 

Hook a timing light up to the plug wire and rev the engine up. See if the light is continuous or flickers. This is an old fashioned way of telling if spark is breaking down.Ecms were a problem on these and yes it could be the source of the bogging,but since you have the manual do the stator,coil resistance checks and electrical trouble shooting tests first.Plus check for any cuts in the coil wire that could short to ground plus check resistance on the plug cap.If the stator and coil check out ok,pull the black cdi kill wire and see if there's any difference.If not then the problem could be ecm related.

 

Might try moving the throttle needle clip up and down since you have tried rejetting most likely won't help but easy enough to try

 

So you are saying that as I rev it the light should speed up and eventually be continuous then? Just want to be certain of what I should see in pass / fail scenarios...?

 

The light should be continuous at low speeds and at high speeds.If light is intermittent as you rev it up,in sync with any engine miss or bog,this could indicate a spark related problem. Like I mentioned it's just an old fashioned way of checking an ignition system to see if it's breaking down. The best tests are still in the manual with the exception of the cdi which has no practical test. Pulling the black wire from the cdi just makes sure the cdi kill circuit isn't causing the problem. Only sure method of checking the cdi is to replace the cdi with a "known good one" as the manual states which was easy for me at the shop,but not for owners. I'm just trying to help you narrow down the possibility of it being stator or coil related along with any other tests the manual shows on electrical trouble shooting. Even after this you may still end up with a possible faulty cdi or ecm that tests for aren't really shown.And it could be either one. That is if you're certain you haven't over looked anything that still might be carb or fuel related which by your first post sounds like you have.

 

Yes sir, very well. I will move forward in a process of elimination with all of the above. As a rookie I may very well be wrong but I cannot fathom a scenario in which it would still lie with in the fuel delivery system. I truly am hopeful I get a fail signal during one of my electrical/ignition tests...
Thank you very much for your insights, I have a renewed hope with your direction and suggestions. Will post follow up.....