Team Primary on Winder secondary mocked up

[fatchance]

I forgot to mention my sled has a backcountry 1.75 ×137 track on it.

What conditions were you running in? That 1.75" backcountry is going to load the motor allot more than a 1.25" typically

 

[1nc 2000]

What conditions were you running in? That 1.75" backcountry is going to load the motor allot more than a 1.25" typically

Groomed trails in lake effect snow area.

 

[KnappAttack]

Ran the 8dn belt today. Tried many different setups in the secondary. I only ran the 240r tune today.
Started out with 35 helix and epi purple set at 0-1. Sled was real snappy and pulled hard, rpm's were right on, belt and clutches are warm. Switched wrap on spring to 0-2, no so snappy and rpm's down a little.
Switched to 41-37 helix purple epi set at 0-1, not as snappy and rpm's were down some. With this helix when I squeeze throttle at 65 mph the belt would chatter like slipping, felt thu the handle bars like a bad vibration. Tried other springs also.
The best set up today was the 35 helix with purple epi set at 0-1. I pushed this set up hard and could not believe how it delivered corner after corner.

I figured you'd like the 8DN with this combo. Same secondary setup I was running with the Yamaha primary and 8DN. 41-37 may need a stiffer secondary spring yet. I'm thinking Dalton Black/Lime with that helix.

 

[fourload]

I see more people are trying the strait 35 with big secondary springs with decent results. I would have thought that combo would put a bunch heat in the belt. I’ll have to give it a try.
I wonder if the primary will need a bunch of weight to compensate?

Yeah me too. Remember last year when the TPI orange secondary spring was deemed too stiff and a belt blower causing too much heat? My head is spinning. I guess all the testing by knowlegable people like Mike will give us the answer.

 

[KnappAttack]

Yeah me too. Remember last year when the TPI orange secondary spring was deemed too stiff and a belt blower causing too much heat? My head is spinning. I guess all the testing by knowlegable people like Mike will give us the answer.

I've done a bunch of driven spring testing on my scale on the drill press with Cat secondary springs and the more popular Yamaha secondary springs, but don't have a TPI orange spring to test, if someone wanted to bring or send one over I could scale it. Just what I've seen though with large Dia. wire on these secondary springs they get seriously heavy on the big end as they wrap up on top. Can't start with much wrap initially on the large wire heavy springs.

 

[1nc 2000]

I figured you'd like the 8DN with this combo. Same secondary setup I was running with the Yamaha primary and 8DN. 41-37 may need a stiffer secondary spring yet. I'm thinking Dalton Black/Lime with that helix.

I like that set up a lot just need to figure out how to keep the skis on the snow.

 

[fourload]

I've done a bunch of driven spring testing on my scale on the drill press with Cat secondary springs and the more popular Yamaha secondary springs, but don't have a TPI orange spring to test, if someone wanted to bring or send one over I could scale it. Just what I've seen though with large Dia. wire on these secondary springs they get seriously heavy on the big end as they wrap up on top. Can't start with much wrap initially on the large wire heavy springs.

Dalton tested it last year. Here is what they came up with. Torsion is at 70 degrees to compare with his spring in that test.

 

[ROCKERDAN]

I figured you'd like the 8DN with this combo. Same secondary setup I was running with the Yamaha primary and 8DN. 41-37 may need a stiffer secondary spring yet. I'm thinking Dalton Black/Lime with that helix.

Mike....Is the black/lime too heavy for 37/35? Are you setting these at approx 24lbs break?

Where does the updated b/o fall when compared to these Cats springs from Dale. I think Dale posted some numbers but cant find em.

thanks
Dan

 

[ROCKERDAN]

If you want a bit of comparison to compare the yamaha spring to the cat you have to take into account a few things. You cant exactly compare or convert the numbers from some arctic chart to some numbers on a Yamaha chart and convert from kg to lbs....they are not measured at the same compressed height but it is fairly close.

Our Dalton Yamaha Chart lists Dalton (Yamaha) and factory Yam sec springs here:

http://www.daltonindustries.com/product_detail.php?product_id=293

You can see that the Dalton YBO spring is a fair bit more side pressure at first than the stock gold sidewinder secondary spring...but almost the same at full compression....the twist you can dictate with the settings you use.

The Dalton White Cat spring ( similar to green cat) is significantly heavier again . I just ran some numbers last night on this to offer assistance

Cat springs are here:
http://www.daltonindustries.com/product_detail.php?product_id=36

for instance,...Dalton White Cat torsion spring
- the first compression load test at a yamaha test height (64mm is close to 2.5" cat test) is 98 lbs (45kg) , ...the 39mm yamaha test height would have the Dalton Cat White at approx 159 which is around 73kg for a direct comparison.

if you put those numbers into the compression columns of the Dalton Yamaha chart. it shows you this spring in relation for side pressure.

....for "torsion", the Dalton White cat spring is around 11 kg at 9-1 setting


If that might help anyone.

Ok I found this from Dale....

This is the White Dalton(Cat) torsional.

So I'll put it here directly.

Dalton White(Cat)- 45kg/73kg
Dalton Bk/Orange- 31kg/52kg

I would love to see Dale do the conversion for his bk/lime too.

Dan

 

[ClutchMaster]

Yeah me too. Remember last year when the TPI orange secondary spring was deemed too stiff and a belt blower causing too much heat? My head is spinning. I guess all the testing by knowlegable people like Mike will give us the answer.

The testing you speak of was on a sled with offset over 60mm.

I’m pretty sure nobody would be opposed if you tried it out and gave some feedback.

 

[fatchance]

Dalton Black/Lime 50kg/82kg same wire as the white spring .207
Dalton Black/Purple 52kg/80kg heavy wire .212

 

[KnappAttack]

Mike....Is the black/lime too heavy for 37/35? Are you setting these at approx 24lbs break?

Where does the updated b/o fall when compared to these Cats springs from Dale. I think Dale posted some numbers but cant find em.

thanks
Dan

Dan,
I've been testing things differently now. I then put in the clutch and set it up upside down on my drill press with a scale under it. I then check the poundage at movement and back off and take the low reading, then go to full shift and back off and take the high reading. Changing 10 degrees you can see the change in side pressure. It takes into account the twist and side force combined.

For instanse, you can make the Black/Lime the same force as the White by just setting the Black/Lime 10 degrees less than the white. The Black/orange is way down the scale and no where near the Cat numbers for side force. IMO we need this added side force of the heavier Cat springs to keep ahold of the belt on the driven.

 

[**sj**]

Mike would you say there *might be this benefit with the OEM clutch and setup....Ive tried some cat secondary springs (fewer coils spread apart) with more side force and thought it seemed all worked better?

 

[Doowithblue]

Mike if the dalton white at 9/1 is approx 11kg-24lb twist what would it be at 6/2? 20lbs?

 

[Doowithblue]

Would also be interested in seeing the new dalton blk/orange @ 9/1