confused with clutching

3/16" ,(10-32),,,,,take weight in with you,,,,,,, will have clearence issues,,,, need jam nuts,(thin) different material or grade bolts will weigh different,,,, yes need gram scale to even them up..........
 

Doyou just use grade 2, or grade 5? Clearance issues? I won't need to grind anything with that length screw and Jam nut correct? Just making sure ahead of time so no questions later.

Also, with a lighter primary spring allowing grab the belt more, will a softer primary spring with added tip weight usually bring down top end rpm?
 
still confusing eh.....lol..I will put my stock setup back thurs or Friday..I have 4.5 in and 5.4 out(washers under rivet) stock springs and helix and let you know what I get for rpm and speeds if possible.Crappy snow out here when it warms up,probably Saturday a better day since it will be colder yet.
I have tried the w-w-w primary with bus..seems like the belt not being grabbed at top as well looking at the black marker I put on sheaves,black is faint and not all removed near top wot. :o| #$%&*
 
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Let me know how that works for ya blue. Rpms will prob be very close, but the stock 47 helix doesn't seem to have anywhere near the pull of
my 52-46 micro Belmont, I will report tomorrow evening with my findings. When I get a scale I will be using the machine screws, washers and jamnut technique for my weights I believe
 
belt will not go to top of sleeve,,,,,,, will run up to 1/2" from top is where its at.........(design)............of the beast.........
 
thank you much for the advice, i really think i have somewhat of an idea of where to go. i know the sled has the potential to be fast as i have seen 105 on a warm day gps with the 52-46 helix with the red spring, but rpm was low, will try green spring and see what happens, and then tune with the primary from there, and try with both green and red spring, and see how it feels for backshift, and what kind of speeds i can get. but i do know that the 52-46 pulls hard!
 
I didn't see it in the posts, so I'll ask. Is your belt new?

Last season was so short I didn't get to dial mine in to get rid of the overrev. It was my first attempt at clutching and if it wasn't for the overrev, I wouldn't have touched it. It's a lot of trial and error! Plus I ended up with a pull through as I was doing it, which really threw me for a curve. Change one thing at a time and document every set up. Like Riverrunner said, get Olav Aaen's clutch tuning handbook. it's very interesting and will provide a lot of good info. It also has charts explaining the impact of various yamaha primary springs, secondary springs, helixes, wraps, etc. (which are also available on here).
 
Tonight went riding, 20 degree temps, fresh 2 inches of snow ontop of a loose base to start, not ideal speed conditions. But with stock primary springs, 8dn-20 weights with 4.5 each hole, 52-46 helix and green spring at 70, rpms were 8600 from any speed, and held 8600 on the nose. Pulled hard, lots of track spin with the conditions though. 96 mph on gps. Clutches were cool. Marker line on primary was 1/4 from top, or slightly closer, so that's good. Secondary marker line was 1/8 from bottom of secondary. Not sure if it can even wear off any farther down... I need better snow conditions where I can run on hardpack to get a good speed reading. Idk of any sleds 121 with 1 inch track could break 100 mph stock with these conditions. What's your thoughts? Belt seems to be shifting out all the way. I think this is as good as I can get. Even with other clutching set ups, when belts at top of primary and bottom
Of secondary at 8500-8600 rpm, speeds would be same with any set up when belts riding like that. Am I correct?
 
Spinner18 said:
Tonight went riding, 20 degree temps, fresh 2 inches of snow ontop of a loose base to start, not ideal speed conditions. But with stock primary springs, 8dn-20 weights with 4.5 each hole, 52-46 helix and green spring at 70, rpms were 8600 from any speed, and held 8600 on the nose. Pulled hard, lots of track spin with the conditions though. 96 mph on gps. Clutches were cool. Marker line on primary was 1/4 from top, or slightly closer, so that's good. Secondary marker line was 1/8 from bottom of secondary. Not sure if it can even wear off any farther down... I need better snow conditions where I can run on hardpack to get a good speed reading. Idk of any sleds 121 with 1 inch track could break 100 mph stock with these conditions. What's your thoughts? Belt seems to be shifting out all the way. I think this is as good as I can get. Even with other clutching set ups, when belts at top of primary and bottom
Of secondary at 8500-8600 rpm, speeds would be same with any set up when belts riding like that. Am I correct?
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sounds good to me, you may be able to go just add a whisker to the rivet head in the primary. maybe a 1/2 gram. I would also try 60 degree wrap and then check, the looser the secondary the faster it will go, as long as it still provides adequate backshift for your liking.
Its not going to shift out further then it already is,unless you cut the clutch faces.
 
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So how it is now, theoretically, whether it's this clutch set up or a different, ideally in ideal conditions, my sled will go as fast as it will with this set up vs others since the clutches are shifting all the way out?

I'll back it off to 60, and if it holds rpm at 8500 and backshift is goof and clutch temps are fine, I'll run it there. It pulls very hard, much harder than stock set up. I am very happy with trail performance. Will see hat it does on a hardpack lake when they set up and we quit getting snow. We are 19 inches above normal for this time of year. I won't complain about that though :)
 
Spinner18 said:
So how it is now, theoretically, whether it's this clutch set up or a different, ideally in ideal conditions, my sled will go as fast as it will with this set up vs others since the clutches are shifting all the way out?
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yes,if all we are talking about is mph. BUT..(theres always a but....lol) it may be quicker depending on how the sec. is holding onto the belt,meaning a tighter sec. will backshift better,could yield the same speed in a given distance but the rate in which it shifts out can be very differnt as far as elapsed time, it may be quicker with tighter or slower, youd have to test.

I am proud of you actually going out and putting the things I told you to actual test and learning for yourself what happens when you change a setting. NICE JOB, now enjoy that sled with the confidence you tuned it in yourself. ;)!

BTW_ if you need to bring the rpm down just a whisker, the "add" to I am referring to is the tip rivet, either dab a wee bit of weld on the rivet head or use a washer thats light on the new 4.5 rivet and make the tip 5 grams. If you start off and its 8200-8300rpm then climb slightly to 8500rpm thats about as perfect as you can get on snow. :2strokes:
 
Spinner18 said:
So how it is now, theoretically, whether it's this clutch set up or a different, ideally in ideal conditions, my sled will go as fast as it will with this set up vs others since the clutches are shifting all the way out
Click to expand...

Sounds real good spinner. I would add a little weight to the tip of the primary. Like mrviper said. This will get you down just a tad. (and you get to try out your new scale:) I think you are on the right track wrapping that green helix to 60 for high speed and more like 70 or 80 for best backshift. This is another reason to add a little more primary weight because you can add some more twist for better backshift. Without going over target rpm,
Yes this is as fast as this setup will provide when you are on your current surface.(I think that is what your asking) But there is alway another clutching receipt.
You beat me to it mrviper!!!
 
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Mrviper, you have no idea how thankful I am for you help, along with everyone elses. I also read through olav aaens handbook once today, made some sense. Need Togo through again. I am getting a scale in sometime early next week, I will use a machine screw, washer and jam nut to fine tune the tip weight so I can be exact and make it easy to change weight. The sled absolutely rocks right now! I'm slowly but surely learning howclutch components interact with eachother. I hope to keep learning my knowledge base. Now when it's tuned as good as it gets, I'll have my hands full with a stock xcr 800 which my uncle rags on my daily for riding yamaha. But knowing he will pull up to me on the lake at 60 mph and punch it, I hope I'll hang in there, or even slip by. Then I don't need to hear himself gloat :) I will surely update speeds with better conditions and results of the xcr when I get out with him.

Mr viper, whammy, River runner, you guys should be proud of the knowledge you possess, and be able to dial in sleds via Internet descriptions and not even seeing the sled go or drive it. Props! Hopefully someday I'll meet you guys in person, I owe some beers!
 
Damn, riverrunner, i just noticed your from Duluth, I live up in Virginia!!! Sounds like we need toget together and ride sometime this winter!! Do you ever come up this way?
 
Im up in your area often I rode there a week ago and have a cabin up on wasson lake north of nashwalk. I rode out of virgina on the taconite over to the cabin on new years eve. If you ever see a 600 srx on the trail up there it will be me.....stop and chat!
 
Sounds like we need to plan some sort of a ride,
Or else I could come down south I suppose, though the snow is really nice here now. Last night rode from Virginia, up taconite and wolf track to cook, across to tower, and iron ore back to laurention and back to Virginia. Every trail was freshly groomed! Don't see many yamahas out in this area. Seen one viper all year, that's it. So If you happen to see a srx 700 with 686 on the windshield, that would be me. Keep in touch!!
 
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