[NMKawierider]

I took it for a ride today and it was topping out right around 39-40 mph. I feel like it used to go faster but not 100% sure. The rpms were something in the 6k guessing 6,400. I looked all over for the 2018 500HO top speed and not finding much. The new ones say 55 mph and one you tube showed a guy going 60 but thinking he had a clutch kit or a tune. I’m wondering if a worn belt would cause the speed to be limited.

In a nutshell...yes it can. The belt's specs should be in the service manual. While there do a full service, cleaning and inspection of both clutches.If all is well look to things like fuel pressure and volume. Filters can and do get plugged quickly sometimes which also limits speeds.

[HereInOhio]

I took it for a ride today and it was topping out right around 39-40 mph. I feel like it used to go faster but not 100% sure. The rpms were something in the 6k guessing 6,400. I looked all over for the 2018 500HO top speed and not finding much. The new ones say 55 mph and one you tube showed a guy going 60 but thinking he had a clutch kit or a tune. I’m wondering if a worn belt would cause the speed to be limited.

In a nutshell...yes it can. The belt's specs should be in the service manual. While there do a full service, cleaning and inspection of both clutches.If all is well look to things like fuel pressure and volume. Filters can and do get plugged quickly sometimes which also limits speeds.

You don’t know what the stock mph is for the 500 ho do you? I just checked/cleaned the filter. I have a new belt to compare, I thought it was oem but appears to be a knockoff so if I need one I’ll probably just order a new one. Will look at the other things you mentioned if the belts not worn.

[Mogleybear]

I haven't experienced it on my 800XC, but I do know that on my previous Polaris 450, when the belt started to wear the top end speed would be reduced.  On my Kawasaki 650, as the belt wore I didn't notice any change in top end speed, but it would "walk" when in gear without throttle input.  Those were my clues on the previous ATV's that the belt was needing replaced. 

[HereInOhio]

I haven't experienced it on my 800XC, but I do know that on my previous Polaris 450, when the belt started to wear the top end speed would be reduced.  On my Kawasaki 650, as the belt wore I didn't notice any change in top end speed, but it would "walk" when in gear without throttle input.  Those were my clues on the previous ATV's that the belt was needing replaced.

Thanks for the info! I really would like to find out what the top speed is for these new to have something to compare it to. I looked at a ton of videos and post but the only one I found was a guy going 60 but that wasn't for the HO and I would also assumed it had some tuning and/or a clutch done on it.

If anyone knows how fast their stock 500 HO went please let me know!

[HereInOhio]

I took it for a ride today and it was topping out right around 39-40 mph. I feel like it used to go faster but not 100% sure. The rpms were something in the 6k guessing 6,400. I looked all over for the 2018 500HO top speed and not finding much. The new ones say 55 mph and one you tube showed a guy going 60 but thinking he had a clutch kit or a tune. I’m wondering if a worn belt would cause the speed to be limited.

In a nutshell...yes it can. The belt's specs should be in the service manual. While there do a full service, cleaning and inspection of both clutches.If all is well look to things like fuel pressure and volume. Filters can and do get plugged quickly sometimes which also limits speeds.

Unfortunately the manual doesn't have the spec for the belt. From what I gather they are 35mm new and should be replaced at 33.5mm but I will call the dealer to see if they can confirm. I checked and cleaned the air filter but will look at the fuel filter. You don't know what the volume should be offhand do you? Or the best way to measure it besides filling up a jar and timing it?

[NMKawierider]

I looked in my manual on my 2015 800 which should be pretty close on fuel specs..maybe a hair higher but in electrical it has the specs in MPa for pressure and Liters per hour for flow rate so: The pressure at .33 MPa, +-.01Mpa is 47.86psi +- 1.4psi Anything outside that range replace the pump. For flow rate its 35 liters per hour which is 1,183.45 Oz per hours or 19.73 per minute..or .33OZ per second...so get a measuring cup that can measure down to one OZ and in 5 seconds it should pump 1.63 OZs. Look in your electrical section for yours.

[HereInOhio]

I looked in my manual on my 2015 800 which should be pretty close on fuel specs..maybe a hair higher but in electrical it has the specs in MPa for pressure and Liters per hour for flow rate so: The pressure at .33 MPa, +-.01Mpa is 47.86psi +- 1.4psi Anything outside that range replace the pump. For flow rate its 35 liters per hour which is 1,183.45 Oz per hours or 19.73 per minute..or .33OZ per second...so get a measuring cup that can measure down to one OZ and in 5 seconds it should pump 1.63 OZs. Look in your electrical section for yours.

Thanks! I’ll check mine out and convert it over if different. For the belt spec I called and it’s 33.5mm I believe new is 36mm. Mine is as 35.7mm so plenty of life left. It started at 40 mph and went down to 26 mph and was a super dusty day. Starting to wonder if the air filter may have contributed. I’ll check that as well as the fuel pressure. After that it may be left to pulling the clutch to see the backside.

[HereInOhio]

I looked in my manual on my 2015 800 which should be pretty close on fuel specs..maybe a hair higher but in electrical it has the specs in MPa for pressure and Liters per hour for flow rate so: The pressure at .33 MPa, +-.01Mpa is 47.86psi +- 1.4psi Anything outside that range replace the pump. For flow rate its 35 liters per hour which is 1,183.45 Oz per hours or 19.73 per minute..or .33OZ per second...so get a measuring cup that can measure down to one OZ and in 5 seconds it should pump 1.63 OZs. Look in your electrical section for yours.

I pulled the fuel filter and cleaned it with no change. I measured the fuel and it was around 44 psi which is pretty darn close to the specs combine with the flow was if anything a little higher than the numbers listed above (15 seconds gave me roughly 6 oz of gas). The machine was only going 26 mph but what was getting me is the rpm wasn't going above 5,500. Even if the belt was slipping I would expect to see it go into the 7k. I rev'd it while not in gear and it did go up to the 7,200 range which has me believing its not a engine or fuel issue but more a transmission/clutch/differential/brake issue. The brakes have squeaked very bad since I got it but when in the air they don't have a lot of resistance.

Any idea what my next step should be? I'm leaning towards jacking it up and quickly checking if I feel the brakes grabbing again which I doubt I will. From there pull the clutch to see if there's something going on with the secondary and replace the belt while I'm at it.

[NMKawierider]

3-4psi under is actually quite a bit. Is it enough to drop the top speed that much...I don't know..for sure it will some. I would do a full inspection and cleaning of both clutches and belt as well as air intake and filter. Anyone do a compression test on this lately? Any possibility that its in need of rebuilt? If you have been running the paper CFM filter on it in dusty conditions...the answer may likely be..yes. People are only getting on average 1200 miles before the top end is gone.

[HereInOhio]

3-4psi under is actually quite a bit. Is it enough to drop the top speed that much...I don't know..for sure it will some. I would do a full inspection and cleaning of both clutches and belt as well as air intake and filter. Anyone do a compression test on this lately? Any possibility that its in need of rebuilt? If you have been running the paper CFM filter on it in dusty conditions...the answer may likely be..yes. People are only getting on average 1200 miles before the top end is gone.

I'll have to look at the gauge I used when I get home, it may have been within spec but I'll check. It doesn't have a paper filter and only has about 200 miles and 75 hours on it. I just cleaned the filters before I rode last and unfortunately I didn't put oil on the outer one and it was extremely dusty out last time riding which I wasn't happy about once I realized. We didn't ride long or hard though and when I cleaned it after it didn't look like anything got through.

I will run a compression test later as well but doubt the issue is with the engine (doesn't hesitate, revs up to rpm just fine, and most importantly wasn't having the issue before getting stuck in mud.) I can't remember the exact details since this was quite some time ago but I wouldn't doubt that I glazed the belt or something tweaked in the clutches. I'll pull them apart and check them out. While in there I saw posts of other people putting on different weights and springs from can am (part # 0901-7103 and 0951-1016) smooth the take off out some. Do you have any experience with those particular ones?

[NMKawierider]

While in there I saw posts of other people putting on different weights and springs from can am (part # 0901-7103 and 0951-1016) smooth the take off out some. Do you have any experience with those particular ones?

I do not. To me this is an engine that although can develop enough power to bring itself into limiter range in RPMs, under load it can not develop enough power to go beyond a certain point. It's missing or lacking in something. There is only so many things it can be and some of that needs focused testing and inspection. Good luck. If the clutches are operating correctly and the preload was set correctly on the secondary, then one looks at valve timing, ignition timing and voltage, air and fuel supply and of course compression. One other thing is it may be on a limiter if it is in 4wd or diff-loc or the reverse light is on.   

[HereInOhio]

Following up for those who may need it. This left off as getting the machine up to 40 mph but after taking it to the trail ones the speed was severely limited again. I had some help today and identified that the primary ramp plate or clutch variator is supposed to have a hex stamped in it to marry with the hex on the clutch shaft and it was rounded out causing the slipping.

The ramp plate I have is no longer available and was superseded with a new part which is more stout. Unfortunately the design uses a different size hex so it doesn't fit on the rest of the clutch. It sounds like these are problematic and I was told not to get a cheap replacement for safety concerns. As much as I would like to get a new design clutch I'm going to sell the machine and don't want to shell out that kind of money for it.

Now I need to find out where I can find the OE ramp plate or at least somewhere that meets OEM spec. If anyone reading this has a primary that they are not using please get ahold of me.
Old Part #:  0GR0-051002    New Part #: 0GR0-051002-000001