Raidernut109
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I believe steve is referring to 15% gear reduction not heat. Although i would assume the clutches are designed to run cooler by design as well
KWI Clutching H2
- Thread starter Cornell Customs LLC
- Start date
It’s been to hot to run the dunes or Moab. That is where you will see the difference, larger tires and more strain on the drivetrain. The slightly lower gearing would help IMO. Running it up and down the street I haven’t seen much difference between the belts. I have the Pro R belt in it now. I don’t know if you have watched any videos of people trying to get the belt threads out of the stock secondary spring and ultimately taking the secondary off. Not to mention using a bolt to spread the sheave. I think the KWi secondary is worth it just for that . Not sure why you are so worried about it. Run the stock setup and see if does what you need it to do and you will have a base line to compare to. The only sure fire belt fix is a Mav R and it has its own set of problems. I am sure the KWI primary is worth the money and I may still end up with it or the Larue or a Pro R Boost. Time will tell, these cars got slapped in the dick and everyone was on hold. My dealer talked to Jim at EVO and they have some cool stuff coming to the H2 for the go fast/dune guys which also means more clutching mods available. Cornell Customs video sells the KWI setup for me at low speeds, plus my dealer works with Kris as well.
I spied on FB that Cornell Customs was testing the Pro R belt for a higher speed situation. I hope he chimes in and helps me out.
Quick recap, I have the Fusion secondary and the stock “new” primary with the KWI/TVM clutch kit with the KWI Hyperdrive cover. Clutch kit is tuned for our sand dunes in Utah, 4500-4900’ or so KWI came out and helped get it dialed for TVM. They sell all their H2’s with this kit as it really needs it. I have broke in both stock belts and Pro R belts.
Observations with the stock belt, stock motor and stock tires and wheels aired down to 10 PSI in 4x4 no lock. Stock cover on without the shield.
One of the big climbs I could only crest the top at 25 mph and 7400-7500 rpm and falling. Could smell the belt but the temp was only 190 on the Kawi screen. Running the dunes I would see 180-190 pretty consistently. No belt slip issues or chatter and the belt looked fine when I took it out.
Pro R belt.
Same set up,only change is the Pro R belt. Same climb I could crest the top at 35 mph and I was at 8K even and it held it to the top. (Supercharged Pro R could be in the 50’s). Did not seem to be hitting the rev limiter. Belt temp was 176 at the end of the climb. Running the dunes the belt was 10 degrees plus cooler than the stock belt. Average was around 174. Not sure if this is because the Pro R belt is longer and better material. The Pro R belt is the best belt in the universe until the Boost belt comes out. Plenty of 500+hp Pro R’s running around. 15% is a lot, but for some reason I don’t really feel it, but the RPM gauge seems to tell me it does exist.
There was one other H2 down there and it was the new silver one. It was completely stock except Pro Armor paddles and wheels. I didn’t let him know he was on a terrible set up and the stock tires would have given him a better chance. Dealers put these packages together ready to go and will add it to the financing. The uneducated buys them up thinking they are good to go. He could not believe I could make it to the top, especially on stock dirt tires. He was lucky to get half way and still have enough speed to turn out. This is the reason TVM contacted Kris to get their clutch kit dialed, it struggled here. My stock x3 could climb this hill around 35 on comp cut STU’s.
I do think this is a great set up, no belt slipping or even getting the factory gauge into the red all day, about 85 degrees air temp. Our dunes are small and not like Glamis where you could have a hour of hard non stop dunning. The only problem I had was it came out of gear going up one of the steepest dunes. It slipped in between gears and made the loudest bang. I thought for sure the new primary had given up. Not sure if it was operator error and not getting it locked into gear. Seemed fine the rest of the day.
One thing I notice with both belts is if you stop to talk with your buddies and turn the machine off the belt temp skyrockets super fast. It would show 205 after being parked with the motor off for just a few minutes. The heat just stays in the case, I started revving it in neutral for a minute and let it idle until the gauge stopped climbing. It would take 4 minutes or so. Not sure how a Razorback would read, but if this is even close you would be heat soaking your belt when you stop for BS and drink break. I am ordering the RPM fan, let it run to evacuate the hot air when I park. It may be usefull in Moab. Taking the same setup to Moab next month, leaving the weights where they are at and see if it can do double duty like my X3 could. If so this will be a great setup for my use. One huge plus to running the Pro R belt is they are everywhere. The vendors all have Pro R belts, but not one H2 belt and you can usually get one for $200 or less.
Cornell, do you think I chase a few more RPM’s on the top? Engagement seems to be around 1800-2200. So hard to tell on the either screen. I would be interested in your findings today since you have the KWI Primary, but I am super impressed with the holding power of the stock primary with the cap and weights so far. Temps seem good as well.
Quick recap, I have the Fusion secondary and the stock “new” primary with the KWI/TVM clutch kit with the KWI Hyperdrive cover. Clutch kit is tuned for our sand dunes in Utah, 4500-4900’ or so KWI came out and helped get it dialed for TVM. They sell all their H2’s with this kit as it really needs it. I have broke in both stock belts and Pro R belts.
Observations with the stock belt, stock motor and stock tires and wheels aired down to 10 PSI in 4x4 no lock. Stock cover on without the shield.
One of the big climbs I could only crest the top at 25 mph and 7400-7500 rpm and falling. Could smell the belt but the temp was only 190 on the Kawi screen. Running the dunes I would see 180-190 pretty consistently. No belt slip issues or chatter and the belt looked fine when I took it out.
Pro R belt.
Same set up,only change is the Pro R belt. Same climb I could crest the top at 35 mph and I was at 8K even and it held it to the top. (Supercharged Pro R could be in the 50’s). Did not seem to be hitting the rev limiter. Belt temp was 176 at the end of the climb. Running the dunes the belt was 10 degrees plus cooler than the stock belt. Average was around 174. Not sure if this is because the Pro R belt is longer and better material. The Pro R belt is the best belt in the universe until the Boost belt comes out. Plenty of 500+hp Pro R’s running around. 15% is a lot, but for some reason I don’t really feel it, but the RPM gauge seems to tell me it does exist.
There was one other H2 down there and it was the new silver one. It was completely stock except Pro Armor paddles and wheels. I didn’t let him know he was on a terrible set up and the stock tires would have given him a better chance. Dealers put these packages together ready to go and will add it to the financing. The uneducated buys them up thinking they are good to go. He could not believe I could make it to the top, especially on stock dirt tires. He was lucky to get half way and still have enough speed to turn out. This is the reason TVM contacted Kris to get their clutch kit dialed, it struggled here. My stock x3 could climb this hill around 35 on comp cut STU’s.
I do think this is a great set up, no belt slipping or even getting the factory gauge into the red all day, about 85 degrees air temp. Our dunes are small and not like Glamis where you could have a hour of hard non stop dunning. The only problem I had was it came out of gear going up one of the steepest dunes. It slipped in between gears and made the loudest bang. I thought for sure the new primary had given up. Not sure if it was operator error and not getting it locked into gear. Seemed fine the rest of the day.
One thing I notice with both belts is if you stop to talk with your buddies and turn the machine off the belt temp skyrockets super fast. It would show 205 after being parked with the motor off for just a few minutes. The heat just stays in the case, I started revving it in neutral for a minute and let it idle until the gauge stopped climbing. It would take 4 minutes or so. Not sure how a Razorback would read, but if this is even close you would be heat soaking your belt when you stop for BS and drink break. I am ordering the RPM fan, let it run to evacuate the hot air when I park. It may be usefull in Moab. Taking the same setup to Moab next month, leaving the weights where they are at and see if it can do double duty like my X3 could. If so this will be a great setup for my use. One huge plus to running the Pro R belt is they are everywhere. The vendors all have Pro R belts, but not one H2 belt and you can usually get one for $200 or less.
Cornell, do you think I chase a few more RPM’s on the top? Engagement seems to be around 1800-2200. So hard to tell on the either screen. I would be interested in your findings today since you have the KWI Primary, but I am super impressed with the holding power of the stock primary with the cap and weights so far. Temps seem good as well.
I would be interested in what your wide open RPMs are at 55 mph on flat ground.
From 20-25 mash it to the floor, we like to see about 8800 RPMs at 55.
If it’s lower you need to remove some tip weight, if it’s full redline you can add some tip weight.
We find this gives you the best performance with whatever tires your running.
I like the ProR belt for the crawler setup as well as my performance setup, I can still hit 100 with either setup on 33” tires.
olliechristopher19
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Yikes!! Financing this?
At least on my stock one I follow the rule of not shutting off the machine after a drive. I let it idle a few minutes. I don't know much about side by sides but assume one of the worst things you can to with "fan blade" cooled rubber belt is to shut it off after a hard ride.
My local Kawasaki dealer has them in stock and I carry a spare just in case. What is the reality of shredding a belt? I'm still under 1,000 miles. I let my rig warm up and cool down and follow the owners manual and common sense.
I'm sitting on the sidelines right now in regards to getting a full on KWI clutch system. I may have to eat some crow but my OEM setup has so far been reliable and nothing more than removing cover and blowing out the dust. Belt still looked new at a few hundred miles. Time will tell......
olliechristopher19
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I'm biased on that fan. I was looking at it and have a concern of it impeding airflow if its were to shut off. I really think Kawasaki engineers did it right with the induction system as is.
I personally would tread lightly when doing any modification that has a possibility of negative impact on cooling. The RPM system will do as advertised as long as it's running. If the blades quit spinning it is a huge intake blockage.
I was looking at Steve Austins rig and it looked like he was using the KWI setup and OEM ducting. I'm pretty confident none of us here are running as hard as he did in the Prospector 250 and Night Vision 250. He is running in the Sportsman class so very limited on modifications.
Sand Shark4
Active member
Can you run the Pro R belt with the stock primary and secondary?
No, it is too long, we have modified the stock secondary to run it, it runs high in the sheave but we have not had any issues running it like that but we don’t have a lot of miles on that setup.
Sand Shark4
Active member
It rides really high on the sheave.
That’s how we get the reduction , we run them this high on the KRX with no issues at all but just haven’t ran it like this a lot on the H2
olliechristopher19
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In your picture of the KWI secondary it does not look like it is running that high up. Are the KWI secondary sheaves bigger in diameter? I'm assuming they are a whole different design. And man I do like the quick spread tool!! Sure looks user friendly for swapping belts.
Yes, the KWI secondary is larger in diameter than the factory secondary, and this picture is of the factory secondary with our modifications to run the longer belt.
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You must not dune and if you do, you don’t dune hard. They all shred belts but the Mav R and YXZ. And you should carry two belts, because once you use the spare, you don’t have one. But you fallow the owners manual so you will never have a problem one, but if you do….
KWI Fusion Clutches are on sale this week only, contact me if you are interested in saving $500
we can get them setup for your needs.
we can get them setup for your needs.
olliechristopher19
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I aged out of the Glamis scene almost 2 decades ago. Dumont over a decade ago. I'm more of a desert and mountain guy. Slow to fast technical trails and open rough desert. And not only follow the owners manual but use some common sense out on the trails.
Of course this could all change as I get used to this rig. I'm cautiously optimistic that there is no reason to blow a belt if you break them in and don't drive like a knucklehead. I also pull my cover off every few drives to blow out everything
My KFX 700 had skat track 10 paddles tires and I had the same OEM factory belt for thousands of miles on that machine. Only engine modifications were pipe and carbs. I ran it hard but let it fully warm up and had very heavy weights to clamp the sheaves with little slip. I'm assuming these UTV's are the basic same function just heavier.
