Bigigviper
New member
I have a 2002 Viper which has Hauck pipes,and clutch kit. The sled absolutey rocks, it has the best throttle response of any sled I have ever rode. It handles like it is on rails too. My question is: My clutches get real hot when I'm into the throttle alot, how hot is too hot? I'm turning 9200 WOT. Has anyone used a torque stop and what were your results?
redsnake3
New member
im in the same situation, awesome response pipes at 9200rpms and the clutch is wicked hot. i do have a torque limiter, i think its a sign that the clutching isnt "on".
Did some clutching on my brothers Viper with Heavy Hitters yesterday, after 5 back to back 500 ft pulls the primary sheaves were just over 100 degrees and the secondary was 85-90 degrees. Both pretty cool to the touch. If your clutches are getting too hot its a sign that your belt is slipping and you need to do a little clutch work 
Forgot to add that his sled does have the Yamaha torque limiter.
Forgot to add that his sled does have the Yamaha torque limiter.
ModMMax
New member
Cool clutches are one of the secrets to best performance. Once they get hot the springs soften and quite working as designed. It helps when things are real clean. I scrub both primary and secondary with hot water and dish soap. Scrub the belt as well. I use a scotch green pad. Replace both springs at least once a year and start looking for ways to get the heat away from the clutches. The secondary seems to get hot first. I punched several 2" holes in my belt guard over the secondary. In many cases, the clutches heat because the gear ratio is too tall. Try a small gear with 1 or 2 less teeth and you will find the clutch heat will be reduced. Hope this helps you.
..SNAKEBIT..
VIP Member
when I went out west my clutches got real hot and blew 2 belts, was running stock spring & 8ek with both rivets out, green secondary spring and 43' helix can I go to a silver secondary spring to add more weight to the primary? or what is the best way to try and cool them down? I should add last year I ran 1.81 gearing this year I have 2.16. any hints or recomendations would be helpful
am I right will adding weight give better grip & help cool the clutches?
am I right will adding weight give better grip & help cool the clutches?
ModMMax
New member
By out west, if you mean moutain riding, then I think you are on the right track with the 2.16 gear ratio. Adding primary weight will reduce your RPM. Use the weights needed to make the engine spin at rated RPM. Increasing the driven clutch pre load will lenghten the upshift time. Gears and driven presusre really are determined by the terrain and your riding style. Most boondocking and semi agressive trail riding benifits from the gear ratio you have selected combined with stock driven pressure and primary wieghts that cause rated RPM. If you continue to heat, its becuase you are calling for more power than you have cooling speed, typical of deep snow riding. If you can figure out how to make them run cool, everything will work better. Millwright's rule of thumb. If you can hold your thumb on it, its not too hot. I have my clutch temps down to where I can touch them. I don't recommend you do this to your belt guard, but it worked for me.
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ModMMax
New member
Ventilated belt guard
If you do this to your belt guard, very serious things can happen. There is a company making a fan driven shroud that mounts to the top of the belt guard and pulls hot air off the driven clutch and exhausts it out the foot well. I have never tried one but I understand they work very well.
If you do this to your belt guard, very serious things can happen. There is a company making a fan driven shroud that mounts to the top of the belt guard and pulls hot air off the driven clutch and exhausts it out the foot well. I have never tried one but I understand they work very well.
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..SNAKEBIT.. said:
A stiffer secondary spring and added weight will help grip the belt better and reduce the temps. A shallower helix and more weight will also do the same thing, but you shouldn't need any shallower than a 43 on a Viper.
Try the silver secondary at 70* and add some weight to the primary to get your rpms right, that should cool your clutches down. Don't cut up your clutch cover just yet, you shouldn't need to do that for most conditions other than deep powder to keep your clutches cool.
vipertripplexxx
New member
For you guys running 9200 rpm.... you need alot of belt tension when running high mph runs! Don't use the standard srx type clutching cause you will get belt slip. You need to use alot of primary weight/force, and low finnish angle helixes to stop the belt slippage. This is why the new four strokes reduce clutch rpm's with gear reduction, to keep the clutch operating efficently. This is really the only way to properly keep sheave temps low...Fix the slipping. Secondary determines belt tension! 100 degrees isn't bad after a couple of long runs!
redsnake3
New member
vipertripplexxx
what about a 52/36 helix from rpc? this is what im runnin and it seems to be pretty good. what do you think?
what about a 52/36 helix from rpc? this is what im runnin and it seems to be pretty good. what do you think?
lets take a look at clutching various ways here, you can have the same results doing things differnt ways when it comes to clutching, big heavy weights, small helix, or you can have the same result, rpm,speed,et,etc with a set up of small weights and a big helix.
The differance is 1 of the set ups will do something better or worse then the other set up will somewhere in the powerband, I am talking about backshift, clutch temps, etc.
There is more then 1 way to skin a cat!!
Remember, if the clutch is hot its telling you it needs attention!!, if its hot in the primary, then you need help in the primary, same with secondary. Just because the tach reads whatever your rpm peak is at wide open throttle, doesnt mean its efficent at transmitting the power to the track, cooler clutch's are slipping less then hot ones are, simple fact.
small helix angles grab the belt harder, they apply more grip to the belt
heavier weights grab the belt harder, but they also require more primary spring force to obtain the correct rpm.
the engine rpm is controlled by the primary, not the secondary, the secondary is to controll the shift.
when using heel clicker weights, you will obtain better results using more tip weight and shallower finish angles. The weights act like a progressive angle helix and upshift very quickly.
a softer primary spring will upshift the clutch's at a faster rate, thus you will need less intial shift angle on your secondary helix, you will use slightly less weight in the primary as well.
when on SNOW, try to keep your engagement speed around 4000rpm, much more and no matter what track you have, your losing traction from a dead stop holeshot.
your gearing plays a role in clutching, the steeper(higher number) a sled is geared the easier it is to pull more weight in the clutch, you make the load easier on the engine, the same thing goes the other way, the less gearing (lower number)you have the more you lean on the motor in the way of load, so if you have a high torq motor you wouldnt want to run it geared real steep.
a softer secondary spring is faster on topend then a stiff one is, you only want enough secondary pressure applied to keep the belt from slipping, you only want to controll the shift, not over power it! anymore then that and the secondary clutch fights the primary by trying to backshift and pull the belt down to a lower ratio. Roller secondary clutch's are the opposite, they require alot of secondary spring, they try to upshift very quickly, you need to use shallower helix's with these, the main problem with rollers over buttons is they try to backshift while on topend, so your topspeed will be slightly less, but they backshift so good, average trail riding is absolutley awesome, throttle response from the engine is drasticly improved.
keep notes as to what weight/spring combo did what, at what rpm, same with your helix/springs, at what twist it did what?, the better you keep notes, the less time you will spend trying things you have already done with either better or worse results. The guy with the best notes, is the guy who wins consitantly at the races, you gotta get out there and test,test,test.
The differance is 1 of the set ups will do something better or worse then the other set up will somewhere in the powerband, I am talking about backshift, clutch temps, etc.
There is more then 1 way to skin a cat!!
Remember, if the clutch is hot its telling you it needs attention!!, if its hot in the primary, then you need help in the primary, same with secondary. Just because the tach reads whatever your rpm peak is at wide open throttle, doesnt mean its efficent at transmitting the power to the track, cooler clutch's are slipping less then hot ones are, simple fact.
small helix angles grab the belt harder, they apply more grip to the belt
heavier weights grab the belt harder, but they also require more primary spring force to obtain the correct rpm.
the engine rpm is controlled by the primary, not the secondary, the secondary is to controll the shift.
when using heel clicker weights, you will obtain better results using more tip weight and shallower finish angles. The weights act like a progressive angle helix and upshift very quickly.
a softer primary spring will upshift the clutch's at a faster rate, thus you will need less intial shift angle on your secondary helix, you will use slightly less weight in the primary as well.
when on SNOW, try to keep your engagement speed around 4000rpm, much more and no matter what track you have, your losing traction from a dead stop holeshot.
your gearing plays a role in clutching, the steeper(higher number) a sled is geared the easier it is to pull more weight in the clutch, you make the load easier on the engine, the same thing goes the other way, the less gearing (lower number)you have the more you lean on the motor in the way of load, so if you have a high torq motor you wouldnt want to run it geared real steep.
a softer secondary spring is faster on topend then a stiff one is, you only want enough secondary pressure applied to keep the belt from slipping, you only want to controll the shift, not over power it! anymore then that and the secondary clutch fights the primary by trying to backshift and pull the belt down to a lower ratio. Roller secondary clutch's are the opposite, they require alot of secondary spring, they try to upshift very quickly, you need to use shallower helix's with these, the main problem with rollers over buttons is they try to backshift while on topend, so your topspeed will be slightly less, but they backshift so good, average trail riding is absolutley awesome, throttle response from the engine is drasticly improved.
keep notes as to what weight/spring combo did what, at what rpm, same with your helix/springs, at what twist it did what?, the better you keep notes, the less time you will spend trying things you have already done with either better or worse results. The guy with the best notes, is the guy who wins consitantly at the races, you gotta get out there and test,test,test.
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ModMMax
New member
You know your way around this Mrviper
vipertripplexxx
New member
Wow, Thats a hellava helix spread! I would think that if you can get a straight shift out of it, you should have plenty of tension up top with a 36 finish angle, and a fairly light secondary spring. What weights/springs/rollers are you running? give us the whole setup.
What rpm's are you running, and at what speed? Clutches hot? Hows the upshift, backshift?
You want just enough tension to stop the slip, anything more is also inefficent.
M2C...Primary determines rpm, secondary determines shift/belt tension. Like mr viper said theres more than one way to skin a cat.
What rpm's are you running, and at what speed? Clutches hot? Hows the upshift, backshift?
You want just enough tension to stop the slip, anything more is also inefficent.
M2C...Primary determines rpm, secondary determines shift/belt tension. Like mr viper said theres more than one way to skin a cat.
redsnake3
New member
yeah its pretty big, its from rpc performance they ran out of the regular angles so thats what they gave me. i run at about 9200-9300 rpms and it upshifts like crazy. running heel clickers grinded weight off to raise top rpms cause it wouldnt reach 9 before. running empty weights except in the shoulder where the weights a secret 
just kidding. i got all the weight possible in the shoulder around 5 grams which is another reason it hauls so hard on bottom. also stock secondary spring. not exactly sure of the speed we run 660' here and i never got the slips at the track this weekend.
just kidding. i got all the weight possible in the shoulder around 5 grams which is another reason it hauls so hard on bottom. also stock secondary spring. not exactly sure of the speed we run 660' here and i never got the slips at the track this weekend.
redsnake, are ya running the grey spring or red??
Good Post MrViper700! Anyone who is going to tune they're clutches should review this info first, it will save you time and money.
I keep a log also, help's when you get older like me and get CRS. I log my race set up's, "normal" riding set up's for local and out of state area's. What the results were, what worked and what didn't.
I keep a log also, help's when you get older like me and get CRS. I log my race set up's, "normal" riding set up's for local and out of state area's. What the results were, what worked and what didn't.
redsnake3
New member
was red couldnt pull enough rpms so runnin grey
Think ya got it backwards, the red is the stiffer spring will pull more rpm's, its a 230-360, the grey is a 230-330. The stiffer the spring the higher your rpm's will be, will allow you to run some weight in the weights instead of empty. The grey will upshift quicker,BUT, you cant run any weight and thats a drawback with h/c's, I have never found the red spring to be outdone by any of the other ones h/c has had, (blue,grey,white)the only thing is, I like to replace them after 2 years in the sled they seem to take a set.
Go back to a red and youll be able to run a little bit of weight in the middle and the sled will go faster, on a piped viper(9000+ rpm), you will have a empty tip hole, but along with a shallow helix it will pull from start to finish.
Go back to a red and youll be able to run a little bit of weight in the middle and the sled will go faster, on a piped viper(9000+ rpm), you will have a empty tip hole, but along with a shallow helix it will pull from start to finish.
redsnake3
New member
it will not pull top rpms with the red spring.
Srxspec
Your #1 performance shop!
I have one thing to add to Mrviper700's post.
After every 2-300 miles I like to wash my belt and clutches in nice hot soapy water! Also buy yourself a stainless steel wire brush and "scuff" the sides of your belt first, then wash it in warm soapy water. I have seen quite a few guys break-in belts improperly and glaze them and then they constantly have hot clutches and under performing sleds. I actually scuff and wash a brand new belt even before it goes on the sled to get rid of as much of the release agent they have on the belts when they take them out of the molds as I can. Just my .02
After every 2-300 miles I like to wash my belt and clutches in nice hot soapy water! Also buy yourself a stainless steel wire brush and "scuff" the sides of your belt first, then wash it in warm soapy water. I have seen quite a few guys break-in belts improperly and glaze them and then they constantly have hot clutches and under performing sleds. I actually scuff and wash a brand new belt even before it goes on the sled to get rid of as much of the release agent they have on the belts when they take them out of the molds as I can. Just my .02