03 500 classic longtrack lost power

[shredder]

Hi Gang.
I am having issues with what has been my most reliable sled. It is a 500 liquid cooled classic I got fairly cheap. It is all stock except that it has a 121 to 136 extension i put on it when I bought it (in 04). At that time i dropped the upper gear down to 19t. It has run fine for years until last year the chain tensioner broke and I had to replace the gears, tensioner, and the chain. When the gearing broke, I had blown a few belts in it trying to get it back to the truck.
This year when I started using it again, it seems to have no power. When I give it gas is scoots along, but wont go over 30mph. When I pin the throttle, it accelerates slowly, but if i ease the throttle up, it accelerates faster (but not as fast as it used to) and it still maxes out at around 30 mph. This sled is good to at least 65mph on flat terrain at 5000 ft +.
Anyhow, I assumed it was clutching since I blew a few belts out on it, so I took them apart and cleaned all the crud out of them. The rollers all seemed good, rolled freely and were round. The buttons seemed ok. they werent too loose or to tight. I did notice that the primary sheaves seemed a little 'sticky', like they needed a little force to move apart and together, so i cleaned it as best i could with a rag and carb cleaner. I think i got it pretty much clean. I am not sure how freely that is supposed to move, but it seemed that it would not be a problem. I know you dont want any play in it or the clutch will be out of balance. I also checked all the pins and weights and they moved freely as well. I also cleaned the sheaves of all the belt grime. it was pretty bad, but is clean now. I also installed a factory belt which I have since double checked the pn on. The belt fits like it should.
Still no power.
Next I thought the plugs might be bad, so i swapped those out as well. The ones in it seemed fine, but i changed them just to eliminate the problem.
Still no power.
Well, ok. So next I thought the exhaust valves might be an sticking so i cleaned them. still no power.
Anyhow , I am wondering what to do next. Is there something else i should have covered with the clutches?
The sled runs like my old 84 phazer did when a plug was fouled, except it idles just fine and the plug is not fouled. Could this be a fuel problem and not a clutch problem?
What should I be looking at next?
I have run the sled the way it is for at least 6-10 hours so if there was a rats nest in the exhaust it should be burned out by now. I guess I could dissasemble the exhaust and check it as well. But i ams still suspecting a fuel issue. Maybe one of the main jets is clogged?
Please help.
Thanks
Scott
I really love this sled. I use it all the time unless the powder is deep and it is too small.

 

[whoisthatguy]

The stator will affect how much juice you can generate to fire the plugs. Stators go out in every polaris, if you keep it long enough. 3000 miles is probably about all you can get out of a lot of polaris engine parts, like the stator. They are not easy to replace and extremely expensive to buy new. Look for a used one with very low mileage, otherwise you may be replacing one bad part with another that is about to go bad.
CDI boxes will also go out and cause problems.
The left side high low beam switch can also go out and cause engine problems. It can be disconnected from the system, and then you can check to see if the engine runs better without it hooked up.
Check the reeds as well. If you lose just one reed, the engine falls flat on it's face.
If you have more than 3000 miles, rebuild the fuel pump with new diaphragms and clean all the grit out of it. High mileage pumps get sand grit under the little round flat diaphragms that causes loss of suction and loss of fuel to the carbs. A typical symptom of a high mileage fuel pump is that it takes more pulls to get the engine started when cold, than when it was new.

 

[shredder]

I did think about the spark. The headlights are real bright. I should also note that the plugs looked good when i pulled them out of the machine. They also both looked similar.
Is there a quick disconnect for the high beam switch?
I will check the reed valves when I pull the carbs.
BTW the sled has about 2000 miles on it.

 

[skis_n_skid]

On the movable sheave binding issue:

I just rebuilt a clutch and rather than spend the money for the special tools needed to break down the spider, I paid the shop (dealer) to break it down and re-torque it for me (they only charged me $10 to break it down and re-torque it). After I put a new sheave bushing in it the movable sheave was binding ever so slightly at the end, and I thought it would be fine since it was a new bushing. At the shop they told me that any binding at all will cause problems. They would not torque it back down for me until I got it moving freely. I had to use sand paper on the last inch or so at the end of the shaft (where the sheave is all the way open) to get it to move freely.

 

[shredder]

On the movable sheave binding issue:

I just rebuilt a clutch and rather than spend the money for the special tools needed to break down the spider, I paid the shop (dealer) to break it down and re-torque it for me (they only charged me $10 to break it down and re-torque it). After I put a new sheave bushing in it the movable sheave was binding ever so slightly at the end, and I thought it would be fine since it was a new bushing. At the shop they told me that any binding at all will cause problems. They would not torque it back down for me until I got it moving freely. I had to use sand paper on the last inch or so at the end of the shaft (where the sheave is all the way open) to get it to move freely.

are you talking secondary clutch? That is the area I think i may be having problems
Is the bushing you are talking about the one that separates the two sheaves where the inner sheave rides on the outer side of the outer sheave?
That is the area I am feeling friction. After cleaning the clutches, I am seeing belt dust marks where those two sheaves and bushing meet. I am thinking i need to replace that bushing and maybe use some sandpaper on that outer sheave to clean it up some more.

I also have checked the carbs and reed valves. they seem ok and the jets are clean