Hello all, I seem to have lost some power on my ATV, ( 2000 Polaris sportsman 500 ) I am only getting 35 mph out of it at full throttle. From reading several postings on this site it appears that my drive belt could be slipping. I plan on changing to a new clutch kit and my question is this: I currently have stock tires and stock exhaust but I plan on changing the exhaust after the clutch kit and I have no desire to change to larger tires so is it ok to buy a clutch kit for larger tires even though I have stock tires? Would that just give me more power to move the current set up or will it create problems having stock tires on it when I bought a clutch kit for larger tires?

Sorry for the stupid questions but I do not want to cause any future headaches but would like to get more power to the wheels. What kind of mods are done to the air box on these units to increase air flow to the engine? I am a total newbie when it comes to modifying stuff and there are so many different ways to do it from all the reading I have been doing. I would like to get way more speed and power throughout the throttle range, looking at a Supertrapp IDS2 Tunable Silencer/Spark Arrestor - Racing Series exhaust and possibly a EPI clutch kit, does this sound like a good combo to give me what I am looking for? Any chance of getting wheelies out of this unit when I am finished? Wow....that is a lot of questions. :-) Thank you in advance for all your input.

Jeff

 

Just putting a pipe on isn't going to give you any major increase in power without biting the bullet and having the head improved along with carb jetting,etc. You have to increase what goes into the engine to realize the potential of what goes out the exhaust! Clutching would probably do as well and other members can suggest different set ups or performance improvements! OPT

 

Thanks for the reply OPT, what exactly do you mean by having the head improved (told you i was a newbie :-) ) I understand about the carb jetting, was thinking of getting that done but if I am going to do that I might as well have the head done as well. Anything else along those lines that will need to be done while it is in the shop? those are improvements I won't be able to do myself or choose not to do myself I should say.
Thanks again,
jhenney

 

To take advantage of an exhaust systems better flow the rest of the engine needs to be "improved" such as the head,carb jetting,etc. Basically some of the things that can be done is head milling,that is shaving off a small portion of the head surface (.005-.010-.020,etc)that raises compression allowing better combustion of fuel, enlarging intake and exhaust ports, larger valves and seats also,BUT if you do that in most cases the carb jetting has to be bumped up to take advantage of the head modification! That's why I said in the first post just slapping an exhaust on for the most part just makes noise without a noticeable increase in power! Complete kits are available for the die hard power guys,but different clutch kits may be what you want and most times cheaper. I've installed a few over the years and some add more low end power for pulling without a large loss in stock speed,some allow for more speed,etc. You just need to research what you want to do and the other members can share what they have done and their recommendations. OPT

 

If that clutch has never been serviced since 2000, maybe it just needs a rebuild, your weights could be stuck, buttons on secondary worn out, maybe the sheaves are glazed or grooved, or the belt is too thin to ride up enough to give you any speed. Give it a good cleaning, lightly sand a swirl pattern into the sheave faces, measure the old belt to a new belt for wear, and make sure your weights move freely and the rollers dont have cracks or flat spots in them. The primary and secondary springs could also be getting a little weak, and not grabbing the belt or allowing the sheaves to move correctly to give you the up shift for higher top speed.

 

I have had this atv since say 2006 or 2007 and have not changed the clutch or any of it components, I am the third owner and do not remember hearing the second owner saying he changed anything in the clutch, the second owner is a good friend of mine so good chance I would have heard about that repair being done. I will pull the clutch cover off and see what awaits me and go from there. What would be a good upgrade clutch kit that is pretty much plug and play or do you have to tweek them all to get them to work good. Is there a good place to get all the parts you mentioned in one kit that will fit my atv so I do not have to guess what I need? Thanks for your help.
Jeff

 

EPI is one of the best for clutch kits, they make "grunt" kits for oversize tires, kits for more acceleration (great for trail riding in the woods) you can get heel clickers, they are a little more work to tune in, but depending on your set up, can give top end back. I only have experience with Polaris sled clutches, but they are very similar to their quad clutches. I bet a good cleaning with a fresh rebuild and belt will get you your speed back.

 

I ordered the belt and pully puller just a few minutes ago. I'm sure that will go along way toward getting my speed back. Any recommendations on what to use to clean the clutch components so I do not cause any problems for the future? If I was to get a new clutch kit and keep stock tires would I get more power from the clutch kit if I get one designed for larger tires? Or will it create problems due to the fact the extra resistance from the larger tires is not there? I may get one just to get more power down to the wheels but will wait on that purchase until I clean the clutch I have and replace the belt and see how it changes things.

As always, thanks for your input.
Jeff

 

Actually, a good scrubbing in hot soapy water is great for getting belt dust and dirt out of the sheaves. they make a clutch cleaner spray, but you can also use brake cleaner,and wipe it off with a clean rag.

 

I thought the buttons where on the Primary also. Dirt Cheap Yamaha, Honda, & Polaris OEM Parts & Accessories – Cycle Parts Warehouse Part #5

Here is 5 stage kits for the Fuji 500 motor. Aaen Performance - Polaris ATV 500

Here is the full fifth stage .