Clutch tools

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fullcoda

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Joined
Mar 22, 2019
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51
Age
63
Location
Naples Maine
Want to rebuild clutches on a 2005 sx mountain viper. New Springs etc. Never done it before. any special tools i would need? Maybe some tips on how to cheaply and easily get a little more performance out of them vs stock? I know that clutching is different for everyone, and what may work for someone might not work for me. Just never done clutches before. Kind of need a starting point. I've prowled thru the forums and tech pages and learned a lot, just so many combinations it gets confusing. Any advice would be greatly appreciated.
 

Lots of people have different combos for Vipers, but a lot of them are for piped setups.
Maybe someone with a viper with stock pipes can chime in here, but not a lot wrong with a stock setup either.
 
What type of increased performance are you hoping to achieve? Lots of variables here. Better top end speed, increased hole shot, smoother trail operation etc?

For most clutch work there are no special tools required. You can normally get away without removing the primary for spring/weight/roller changes. You will need a torque wrench to tighten the primary bolt to spec...85/45ft.lbs I believe...
Otherwise, 8mm and 10mm sockets, Allen keys will have it covered.
 
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I weigh about 225 so it's probably ok stock the way it is, from a standstill @ 4000rpm it tries to lift the skis and digs a deep trench with no hesitation, which isn't bad for a 144" track. Top end about 100 mph, top rpm @ 8500, mid range has plenty of punch, no backshift problems. I guess that's as good as it gets stock. I bought it with no idea of its history, so I pulled the skid and replaced what was needed, cleaned the power valves, rebuilt the brake, new exaust y, and gaskets, rebuilt the carbs, and so on. Then I thought I would freshen up the clutches, replace rollers, springs, buttons, and whatever else is worn. (man's innate urge to tinker with stuff that probably didn't need it). My real question is how much spring pressure is in the secondary clutch. Can this be done by hand or do I need something to compress it with? Primary too? Going to dig into the chain case too, any thoughts on stock gears?
 
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all the stock clutch springs can be compressed by hand. from the sounds of it, new secondary clutch buttons, new primary and secondary springs and check all the bushings is all you need.
 
Sounds good, want to tear down the clutches just because i never have. Gonna stay stock for now. Don't really need the pipes, but, gotta love that triple triple sound. Thanks guys.
 
Tore it down and yup the buttons were worn. ordered a new spring and buttons. The helix is an 8Bv51 which i think is a 45 degree rise. The spring was in holes #1 and #6. The color was gone from the spring, i assumed it was stock so ordered green. The snow wasn't packed, however, no hesitation on the throttle. She grins every time I punch it.
 
What kind of snow are you riding in. I.E.: trails, ditches, groomed, <1 foot of snow, >1 foot or snow, mountain, etc,etc.
Your secondary currently has the wrap set at 70. The 6+1= a wrap of 70. A drop to 60 would lessen the trenching. Backshifting would get better yet but top end could suffer slightly.
A straight 43* helix would also lessen it. Top end would increase. An 8BV3? would be a 43*. An 8BV1? is a 41*.
 
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A misunderstanding I think. She trenches when I want it to. Like it should. Sled very responsive from a crawl to wot. Very happy with overall performance. I usually ride groom in 2 to 4 feet of snow, with some lakes to play on. I know I totally have the wrong sled for this, (700 triple deep powder special mountain viper) but I wanted a 700 triple two stroke. When this sled was presented to me I fell in love with it, so I bought it. I actually tuned the carbs to reflect my true riding environment. Have you ever played with the multi angled helixes? I'm kind of looking for a little more top speed, but I don't want to loose the bottom end punch. I've been thinking about re-gearing it. Any thoughts on that?
 
That track is going to be your limiting factor for top speed.
Multi angle helixes can get the shift to happen quicker, while still allowing RPM up top.
Unless you have an clutching guru tell you what to try, I would stick with what works.
But, If you are not riding mountains, gearing up a tooth may not be a bad choice.

Your current gearing should be a 21/40
 
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I think I'm gonna stay with the 8bv51, it's pretty aggressive and the shift out and backshift are as good as I need. I don't see any gains in top end speed. As for gearing up a tooth, I should have enough slack in the current chain, yes? I see how the clutch may bog the engine a bit with a bigger gear, so do you suggest that I should put a lighter rivet in the tip? Would this increase engagement rpm?
 
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