I am an idiot --- please help me with Powder clutching!!!!

Honestly for one trip I wouldn't be afraid to run a 45 and see how it goes. Worst case is you have to tighten the secondary up a hole or two. So many ways to clutch a sled. I remember when we were setting up that 2000 srx. He was moving to MT for work so we spent a few days in the garage doing whatever we could to make it eat snow. Got the clutch setup from a guy in Canada that did yamaha motors and rode hills. Kid went into the dealer in Bozeman and told them what he wanted and they almost convinced him that it wouldn't pull that much weight. Well it did and it worked great. Too bad the suspension mods were a little off and he spent the first day buried in a creek bottom all day. Thing would get stuck going down hill. Oh the things we learn by trial and error.
 
Do you have reverse? If not, i have a 43 tooth bottom gear... I have reverse, so i am stuck with the 40 bottom hence the reason for me going to a 19 on the top.
 
Hey Ryan, Dirtjumper, and Stagggs!

Maybe I should just leave well enough alone for 1 week of riding out there...... For the most part, I like my clutching a lot now, so why risk screwing it up! Per Super Torquer, the red spring is supposed to allow for quick back shift. I've never had issues here in MN (about 1,500 to 2,000 feet above sea level) but I just got to thinking that at 10,000 or above things will behave quite differently.

I looked at that black spring again and can't see any other markings.... but who knows. It is moderately dusty on that spring and I'm probably just not seeing other color markings. Maybe I'll really examine it this weekend.

I would imagine my gearing is stock, b/c he never said anything (Geeez, that was 3 years or so ago now!!!!) about messing with the gearing, but how would ya ever know...... But I bet my gearing and secondary are all stock now that I think about it. Sled does not have reverse.

Thanks for all the really useful info.!

Mike
 
OK, so I just got off the phone with Randy at Super Torquer. I described what I had in there and he said my set up is their standard Mnt/powder set up for Mnt Vipers........ 40-10 Heel Clicker's with HC's big red spring. He said he figures right now I have 4 to 4.5 grams weight in HC shoulder with no weight in tip, if kit was installed correctly, which i believe it was. if so, my secondary is completely stock. Super torquer/HC never made a black spring, so that one has to be stock Yammi.

For around here though he recommended I get that red spring out of there and install the grey spring with 4 grams in the tip and 4.7 grams weight in the shoulder. He said I'm most likely over-reving right now around here with that red spring. He also said I'd be crazy to mess with the secondary or stock gearing no matter where I ride.......

Now I'm even more confused!!!!!! but I know what I now must do: This weekend I'm gonna check my whole primary clutch out to see if everything is per his kit. Then I'll at least have that piece of mind and know where the sled is at, and I can make changes from there.....


Damn clutching is confusing business!!!!!!

Mike
 
hey mike just to give you an idea of what you're looking for on the secondary spring color:
DSCN1655.jpg

this is a silver, as you can see dead center is the marking, not big to begin with and it gets scraped and worn away over time
DSCN1654.jpg

here's a green installed, again partially worn away, and as you can see depending on which holes your in it could be behind the post or helix ramp, hope this helps some
jeff
 
I dont know what RPM your pipes are supposed to run, but I would be very very supprised if you can pull the proper RPMs at 11000 feet with the weights empty. One other thing, dont ever use the gray spring, it doesnt have enough finish rate, especially in a piped viper.
 
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Wow, I'm hoping that I mis-read, and I'm sure you don't want to hear this... but did you say your sled will do 100mph on the top end and engages at 45-4800 rpm? That sounds to me like it is geared for drag racing, NOT mnt riding. My viper with stock gearing will top out at 85mph...and I'm considering gearing even lower to see if I gain more torque and get higher track speed when climbing. Mine engages at the stock 3800rpm's. Like someone else said, a high engagement just blows a hole and gets you stuck. I'd be very curious to hear what gears you're running. You need to know what peak rpm's you're getting, and also what track speed it pulls when climbing in untracked powder. Mine bounces from 48-51mph. If you're geared as tall as it sounds, I'll bet the track speed isn't very good when under load in the powder. Bet it's a drag racin son-of-a-gun, though!

SLP specs for 9-11000 feet: 40-21 gearing (stock)
g-w-g primary spring (stock)
8dn-10 arms, 13.3mm (3.1g) rivet inner hole
43 degree helix
green secondary spring (stock), 80 preload (I prefer 70)

I would stay away from the helix with a 41 finish angle. I called SLP a while back and asked them what multi-angle they would recommend. They said absolutely don't get anything with a lower finish angle than 43. They also said they would go with a short spread, like say a 47-43 degree. Their chart says anything under 6000 feet they recommend a 47degree, anything over that, a 43 degree.

Hope I haven't freaked you out, sure this wasn't what you wanted to hear.
 
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Thanks Mod-it! That was actually incredibly helpful.

I certainly need to definitively find out what my actual engagement is, as that was more of a guesstimate. I hope my sled actually engages lower -- more like sub-4,000's rpm's, like yours. I just need some snow so I can get her out of the garage and find out for sure! I bet it is lower.

I have every reason to suspect my gearing is stock, as is secondary. If all he added was a HC 40-10 kit, then per Super Torquer he wouldn't have touched stock gearing or secondary. Their kit only modifies the primary with a mountain spring and adjustable weights.....

Once I can get my Mnt Viper out in some snow, per your advice I'm also going to try and decipher what my Peak HP RPM's are and what RPM's I'm at in powder. What is your sled's peak RPM's???? What RPM's are you hitting when you are climbing at 48-51 mph in the untracked powder????? If you can recall, please let me know....

But of course, I'm 7,000 - 8,000 feet lower here than elevation in mountains of western Wyoming.....

But my top end does seems a bit high. My dream meter reads 100+ on the top end, but this is not radar tested, and with track spin who knows what actual speed is. But I believe it to be higher than 80-85 actual mph.....

It seems like dropping to a straight 43 degree helix (from 45 degree) with a 70 degree or so twist would help some....

Again, thanks to everybody for your thoughts on my clutching dilemnas!!!!!

Mike
 
I wouldn't take for granted that the gearing is stock. The only way my sled would ever do 100mph is if I jumped it off a cliff, lol. I believe you said you bought it with triples already on it. It is possible the first owner thought that since he was adding so much extra hp, he would be able to pull taller gears. Either your speedo is way off, or it is geared higher.

As far as my peak rpms...SLP pipes peak hp rpm is 8900. My sled pulls about 9000 or a hair more out on the trail, but when in powder under maximum load it drops right into 8900 and will hold it. This is what you want to shoot for...I had to change rivets about three times before I got it right. Mine did change quite a bit when I added the flo-rites. Be aware, going out west and riding powder with triples on your Viper is going to make the notorious triple piped powder bog rear its ugly head, check out the last page of the thread "the infamous powder bog" in the Mnt riding section to see the cure.

You should also consider your jetting, it will be pig rich going from the lower elevation you ride to 9000'. With the stuff I've done to mine, I ride around 6000', my jetting is ironically all stock settings. Mains are 156.3, needles are 3.0 position, and pilots are 45's...all stock settings. My fuel screws are 2 turns out, instead of 1-7/8 turns stock setting.
 
OK Mod it, I had the Mnt Viper out today and I discovered it engages at a little over 4,000 rpm. Do you think that is too high? It is just over 4,000, probably not even 4,100.

Thoughts?
 
I wouldn't worry about that too much, not much higher than stock.

I would worry more about what peak rpm you're hitting, and what track speed is when climbing in untracked powder. Your 100mph top speed is what concerns me the most. Your track speed when climbing will be the tell-all if the gears have been changed. No reason why your sled shouldn't pull the same 48-51mph that mine does.
 
So when your "floating" throught the powder or up a hill, your sled pinned WOT just maintains a steady 8900 rpms? Is that what I should look for? I'm just trying to figure out how to test for what my peak rpms are.........

I just dropped the sled off at Carver Performance today for Fox Float install on the front. I wanted all the way around, but Float won't fir into aPro Action skid in the back I guess...... So he's gonna see what he can get to fit....

Mike
 
Ohlins are nice:) I've got a Walker air shock I'd give you a good deal on if it would work. We'd have to measure and see how close they length wise.

As for the clutching gearing issue. Ideally you want it to pull peak r's all the time when pinned and climbing. Playing in the pow it's on and off the throttle so backshift and throttle response are good, but on a climb you need r's to maintain upward momentum.
 
Your rpm's should always hold steady when at WOT, if they bounce around something is wrong. I've read about lake racer set-ups on here that shoot for a little under and then slowly climb to peak, but on a Mnt. set-up you want them to constantly hold peak rpm under load (to my knowledge). Mine will go to 9000 when I first hit it, but then settle in and hold 8900 for as long as I'm climbing or keep it wide open in the powder. I'm far from being an "expert" on clutching, but I'm extremely happy with the 50mph average I get when climbing. I've run into few other 144's that can climb with my sled, so something is working right. AKMountainViper is getting the same track speed with a 151 under his, I'll bet it really gets around good. I haven't seen him on here for a while, but he would be an excellent source to talk with.
 
Hey Mod It, thanks for the advice..... Once I get the sled back, and we actually get some deep snow, I will see where my Peak RPM's are at. Right now we hardly have any snow, so hopefully we'll get some snow accumulation soon.

I can then also re-check what my top speed is. This year I'm going to check with GPS rather than the dream meter, as I want to know for sure. Mod it, you believe it should top out at low 80's mph, right?

Carver thinks he has an Ohlins shock that will fit on the rear, so she should be a much more comfortable ride!

Mike
 
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mod-it said:
Your rpm's should always hold steady when at WOT, if they bounce around something is wrong. I've read about lake racer set-ups on here that shoot for a little under and then slowly climb to peak, but on a Mnt. set-up you want them to constantly hold peak rpm under load (to my knowledge). Mine will go to 9000 when I first hit it, but then settle in and hold 8900 for as long as I'm climbing or keep it wide open in the powder. I'm far from being an "expert" on clutching, but I'm extremely happy with the 50mph average I get when climbing. I've run into few other 144's that can climb with my sled, so something is working right. AKMountainViper is getting the same track speed with a 151 under his, I'll bet it really gets around good. I haven't seen him on here for a while, but he would be an excellent source to talk with.
Click to expand...


Just curious...What drivers are you running + what gear ratio are you using?
 
I'm completely stock: 40-21 gears and 8-tooth drivers. I think that comes out to 1.90 gearing, and with the 8-tooth it is like 2.14. I've always figured I get such decent track speed climbing because it was geared to pull a 144 with only 119hp. With the triples and flo-rites now, it should be shading 150hp.
 
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