so i checked the airbox and tube running into the carb for any leaks, and found none. even put some extra material in the air box lid seal to eliminate the possibility of the seal being worn down. the bike pulls till about 15 mph and then the power fades away, slowly climbing to 32 mph. fuel filter had no cracks in the gaskets so i figured that couldn't be the problem. float level was right at 13mm just as it should be, and since the spark plug suggests this is a lean fuel problem i took the main jet needle out one clip to richen it. still nothing. Next on the list were the valves! whooooooppie. Off came the front end and valves were great, just a little tightening on all four of them, i would say even adjustment for the exhaust and the intake. Looking at the diagrams i realized i had the chain one link behind, or to the left, of the dots on the sprocket. changed that back so it matched the pic in the book and humpty-dumpty went back together again. to my great excitement, there was no major change in performance, maybe a bit smoother deceleration at best. I read that the spark plug is best read after six miles of riding under mid throttle, so thats what i did (i bet my neighbors love me right now). Six miles later the plug was tan around the base ring, but only sooty for not even 1/4 of the ring, including the ground strap.

since there should be at least 3/4 of a soot ring this is a lean condition, and possibly the main jet slide isn't even opening for some voodoo reason?

I was really hoping to have it for a trip in a few weeks, any other ideas are very appreciated.

 

You've concentrated on the carb and any leaks,but have you checked into the clutches,belt for wear,plus in the drive clutch there is a plastic jam nut(limiting nut) that can back off. Item #8 Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse
Another thing is you didn't have to reposition the cam chain as the two plated links will not stay on the two"dots" on the sprocket once the chain makes one revolution.This is just for initial cam timing purposes. If it's not carb or clutch related it could be early signs of exhaust cam wear not opening the valves fully to allow full power or even an electrical breakdown when it's gets warm. Look over this link to a pdf manual, shows measuring cam lobe height(can be done while installed) and also shows electrical resistance on the stator pulse coil and main charge coil.Index of /ORV Manuals/Polaris/Sportsman/1996 - 2001

 

OPT,
I checked the cam and the lobes are fine, slight scaring but no wear down and they open all the way.
For the stator resistance, my meter was on 2K, I'm assuming this moves te decimal 3 places as I got .521 for green and black/red (book says 446)
.006 for green and red (book- 1.6)
And .243 for white an white/red (book says 97)
I'm not 100% sure if when it was replaced a few ears back if it was aftermarket, I think it's oem though. Battery was around half charge when I took these and since they're so far off does that hae any effect on it?
Thanks for helping me through this!

 

Pulse(pick up coil) is way out of spec.Even if you replaced it several years ago they can still start to short out internally. One thing you can try is to do what this guy did and see if it helps,if it doesn't Ricky Stator has pick up coils for 39 bucks.http://forums.atvconnection.com/pola...ml#post3155476
http://www.rickystator.com/catalog/p...oil-p-328.html

 

New pulser coil just installed along with a now clean and shiny flywheel. Resistance is now at 109 ohms and still no change in performance. I don't know if I mentioned it before but the problem is no longer intermittant it is constant. The clutches seem to be in order, and do not drop in all the way, the drive clutch doesn't push the belt to te top of the sheve, it gets it about and inch or two from the top, and this is also when the slow acceleration comes to a standstill. Is there any rev limiter system that could be causing this?
Thanks

 

Sounds like you may have had multiple problems. The limiter is built into the speedo on this model,first year on this I believe. If you haven't addressed the clutches,you might start by just blowing out belt dust and check the belt for any glazed,burnt spots and any worn buttons on the front clutch and roller buttons on the rear clutch.Sometimes a simpler cleaning,belt change if needed will help.Plus don't over look the plastic limiting slotted nut on the front clutch.I've had these back off and clutch travel will limit.

 

The speedometer has 40 hours on it, had to get a new one a year ago or so. A few little pieces rattle around When I shake it?....the old one does to. New one is fully functional though. Also the belt is new and has about 20 hours on it just like the clutches. Buttons rolers and weights and weight pin/screws are all new. In addition the back rollers were drilled out to .375 in a chuck on a lathe where I work and we made up some brass bushings to reduce the slop on the quarter inch screws they sit on. So the back clutch is moving another than stock now haha.to heck the front clutch but I don't have to take te spider off the main sheeve do I?
In neutral the bike doesn't have the power like it should, and it's just spinning the clutches...

I can't thank you enough for the help on this. Just wish it wouldn't be so complicated :/

 

Just make sure you mark the front clutch cover to the back so you can reinstall it properly. Take the front cover off,the spring will come off with it. Make sure the white slotted limiter nut is tight and hasn't backed off.If the 6 buttons are good,the nut hasn't backed off,the one way bearing and fiber washer is ok and after you reassemble and the clutch pushes in and fully extends out(with out the belt on)it may not be a clutch problem,but electrical or even a carb problem that can cause limiting. I still wouldn't dismiss the new pulse coil and double check the setting as I posted earlier as this member found. http://forums.atvconnection.com/pola...ml#post3155476

 

update
the clutch doesnt have the limiter nut...probably got broken off when one of the belts blew up. no wonder i was so confused what you were reffering to haha.
and the new pulse coil is .025 away from the flywheel. book says .016-.030 and being new i would prefer if it didnt get smashed haha. i also took the flywheel off and sandblasted it. Also went through some old emails and the stator is two years old, Caltric that my dad got off ebay for about a hundred bucks.

compression test is scheduled for tonight, till then the bike is in time-out (maybe its attitude will change) hahaha
i really dont know how many miles the bike has on it but whats the average that the piston rings/head and the wall needs to be redone at?
one again thanks a bunch!

 

Compression on the 500 can trick you! On average you'll get is between 65 to 100ps on compression.Look at what your manual says. This is because of the cam exhaust decompression device that allows the exhaust valves to open a little while cranking. "If" taken care of, good maintenance,correct synthetic oil used(0w40,5w40,5w50) this engine can last for many years..