CVT clutch q's

[lt250rdude]

I'm wanting to upgrade both primary and driven clutches on my machine, 94 max IV 6x6. I think the primary is a salsbury 780. It has o ringed rollers. Not sure what the driven clutch is, cant find any markings. The primary has a broken piece inside, what I think is one of the 3 spider guide rods, so I want to upgrade it if possible. 20hp vanguard. Is this a tapered shaft or straight shaft, what other clutch will fit? Will a polaris p85 work? and will i need to match the driven clutch to it? Not finding much info to help me. Thanks

[thebuggyman1]

IMG_0744.jpgUnless your driven is worn out....just replace the spring with a red one from the factory $25 here's the difference.


For the primary, this is what you should have: 302405A-W2 - 780 Series Drive Clutch for Recreatives Ind Max ATVs | MFG Supply
You may want to upgrade to this..it has 6 pucks to grip the belt better: 206095A - Model 94 1" Bore 1 3/16 Belt | MFG Supply

[JoeMeg]

Thanks for posting these links Jim. This will certainly save someone who's not real savy when searching for these items,(me ), a lot of time.

Joe.

[racerone3]

The 94c that you posted will not work well with the red spring driven unless you go with MUCH heavier weights than it comes with stock. I put one in my tank trainer with the old 2 stroke (yellow) spring and it worked ok, but didn't have enough weight to open a red sprung driven when I upgraded.

Also, NEVER ( EVER EVER EVER!!!) run a Duster (Like the 94c) on an engine turning anything above factory governed RPM. The weights aren't anchored to anything and WILL fly out. I'm still missing one weight , and had 3 good sized holes in the tub where some of the others made their own exit path!

[lt250rdude]

My driven is def wore out. I think i'll go with the same as what I got, just change springs. Thanks for the links. What do I have for options on primary springs and weights?

[thebuggyman1]

The driven can be found used...I think I have 3 or 4 laying around... Used primarys are a little harder to find.
Changing the springs and weights gets more complex......I think member Lewis has a friend at a company that does a lot of that

[lt250rdude]

Ok, Thanks Jim. I'll be posting in the want ads soon for one. Also I read in another thread the 780 was only rated to 16hp, I have a 20hp vanguard, should I look for a different model primary? Does the primary have to match the driven?

[Tomo]

hi
The 780 primary clutch was used by recreatives until recently on the 23 hp kohler with out fail .
They also used the 780 driven
Max rpm is 5500
Recreatives changed due to supply issues in regards to salsbury/ comet parts etc

tomo

[thebuggyman1]

hi
The 780 primary clutch was used by recreatives until recently on the 23 hp kohler with out fail .
They also used the 780 driven
Max rpm is 5500
Recreatives changed due to supply issues in regards to salsbury/ comet parts etc
tomo

After Brians post (Racerone3), I was going to ask him what he was using on his monster bigfoot (hustler980) with the briggs bumped up to about 40hp.
Also Lewis is putting a 50+hp briggs in his.....I wonder what he's using. http://www.6x6world.com/forums/engin...tml#post102278

As for the secondary, There were differences in the ramp angles between the 2 strokes and 4 strokes. I don't know which is better to use, or how the rampchanges the rpm advancement of the belt. Purely a guess, but I'm thinking a longer ramp means more twist against the spring, and slower advance. Has anyone tried putting more twist on the spring?

lt250dude; You want a 7" primary (some say 7 1/2") and a 9" secondary (some say 9 1/4"), stock belt is 1 3/16 wide. As the belt wears it changes your ratio because it sinks deeper into the secondary. Read this ATV and Snowmobile Belts - by Dayco
When you say your secondary is worn out....if it is just the rivets that are loose, you can put a spot of weld on them.

[lewis]

The clutches i have i ordered from Quality Drive Systems. Roy is his name, he does this for a living and is damn good at it. Whipper informed me of his business and i have been completly satisfied since dealing with him. Hard to find belts he either has them or knows the number of the belt to order. He is in Ca. so he is 4 hours behind us on the East coast. Tell him what you have, what you want to do with it, and he will guide you through the process. The right clutches make all the difference in the world with the way your machine performs.

Here is his link: Use Phone number listed
Quality Drive Systems

[Meinfield]

Hey Guys, I have been running a comet duster drive and driven clutch set on my Hustler 980 for 3 years and never had any problems. The engine is a highly modified Briggs Big Block putting out 60+Hp and turns 7K+ rpm. I used to take apart the clutch on a regular basis to inspect the pucks, but they were barely worn so I quit inspecting. I like the fact that you can purchase different spring and puck sets for the drive clutch, and the driven has different spring tension settings do you can really dial in the rpm range that the clutch opens. I have a 1200 rpm set in the drive (the Briggs has loads of torque), and the driven is set pretty light so the machine accelerates nicely. When I was running the 25" ASX tires (about 50 lbs each with the wheel) I set it up just the opposite and the clutch allowed for lower "gearing" for a longer period of time. I did have to bore the driven clutch to fit the output shaft on the T-20, however. Even though the factory rating is only about 40HP and 5K rpm, This is a really rugged clutch at a good price, IMO.
Hope this helps!
Chris

[JoeMeg]

The clutches i have i ordered from Quality Drive Systems. Roy is his name, he does this for a living and is damn good at it. Whipper informed me of his business and i have been completly satisfied since dealing with him. Hard to find belts he either has them or knows the number of the belt to order. He is in Ca. so he is 4 hours behind us on the East coast. Tell him what you have, what you want to do with it, and he will guide you through the process. The right clutches make all the difference in the world with the way your machine performs.

Here is his link: Use Phone number listed
Quality Drive Systems

I too have delt with Roy at QDS.Aquired nylon sliders for a secondary that I could not locate. Sent him a drawing with basic dim's and he contacted me with the info. I can say only good things for Roy and QDS.

Joe.

[lt250rdude]

Well, you guys have alot of useful info and have answered all my questions for now! I think I will talk to QDS and make my decision after that. I just want my machine to perform very well without spending a ton of money trying to figure out what works for me and what doesn't, and thanks to those who have!

Buggyman- Im not exactly sure what is wore out, but if you were to grab the driven by the outside you can rock it to and from the transmission. The play is not the input shaft itself. The sheaves are also rusty and kind of pitted, the little black pieces are bad, not so good spring, and just looks terrible! lol

Thanks- Matt

[teeko]

Clutch tuning is very difficult to do well, if you don't know what you are doing. Talk to others and see what they are running. There are so many variables like horsepower, engine rpm, weights, helix angles, springs the list goes on. I recently changed my clutches on my polaris indy only to have the motor lock up. Turns out the changes I made affected the engine rpm. Instead of running 7800 it was running at 9300. This was enough to spin the crank on the pin and rub the case which caused the motor to lock up. I had it rebuilt 3 times before I realized what was happening. A modestly priced upgrade turned out to be an expensive lesson. My sled is currently at a shop with an old school mechanic who learned much of his craft in the 70's racing sleds. As soons as there is enough snow, he will get to tuning it. Clutching is the single most important thing for putting the power to the ground. You can have 100hp, but if it isn't clutched properly, your machine will still suck. All the shops in the area used to drag the sleds every weekend and this guys sleds would beat every other sled every weekend. Some of these guys had thousands into their motors and all he did was tune the clutches! They would race every saturday and every monday, they were swamped with all the losers sleds wanting their clutches tuned.
You can pick up the 'clutch tuning handbook'. This was written by a guy named Aeen. A very informative read. I would not recommend playing with your clutches without at least reading this book.

[cclingma]

Hey Meinfield

I think you inbox is full. I didnt want to hijack this post but had questions about why you USE TO run the highly regarded ASX.