Aftermarket Clutch springs?

[MikeWalters]

Not much for clutch springs available here from Yammi, and they want $55 for a secondary spring.

I can get EPI in town here, but cannot figure out their conversion to yamaha charts..? Yammi is listed in KGF/MM, and only gives one figure unlike EPI, Dalton, etc who list their springs in 2 separate load ratings (I assume they are partially and fully compressed #'s)

They list the 2.5" load and 1.25" load ratings in lbs http://www.erlandsonperformance.com/mm5 ... yamsprsnow

YDR12 Black - 64/118
YDR14 White - 51/90

Also they list Phazer specific
YDR14 - 63/91

I have the Vmax600 secondary with 41degree helix.

The clutch I bought has unkown miles on it, and the green spring is a bit light I think for my application. EPI springs only cost $26 cdn here, half the price as Yammi (who do not have stock anyways), which is why I am thinking of going this route.

I assume their clutch kit for Phazer must be for stock power and track, so I was guessing the black spring they list which is a little stiffer than their Phazer listing might be OK..?

Just eliminating problems before they start (new spring and helix buttons)

Thoughts from any guru's here? Where is UPBushman when you need him LOL

 

[UP bushman]

Not much for clutch springs available here from Yammi, and they want $55 for a secondary spring.

I can get EPI in town here, but cannot figure out their conversion to yamaha charts..? Yammi is listed in KGF/MM, and only gives one figure unlike EPI, Dalton, etc who list their springs in 2 separate load ratings (I assume they are partially and fully compressed #'s)

They list the 2.5" load and 1.25" load ratings in lbs http://www.erlandsonperformance.com/mm5 ... yamsprsnow

YDR12 Black - 64/118
YDR14 White - 51/90

Also they list Phazer specific
YDR14 - 63/91

I have the Vmax600 secondary with 41degree helix.

The clutch I bought has unkown miles on it, and the green spring is a bit light I think for my application. EPI springs only cost $26 cdn here, half the price as Yammi (who do not have stock anyways), which is why I am thinking of going this route.

I assume their clutch kit for Phazer must be for stock power and track, so I was guessing the black spring they list which is a little stiffer than their Phazer listing might be OK..?

Just eliminating problems before they start (new spring and helix buttons)

Thoughts from any guru's here? Where is UPBushman when you need him LOL

Here I am, don't know on those primary springs what would work. I have several setups that work for deep bush or crossover. Right now I'm running primary spring Yellow Gold Yellow 33-211 LBS part #9050-1557G5. Secondary YVX spring is Green part #90508-556A7 at 50 degree twist that equals 17LBS on a fish scale. I have STI clutch arms at 47.5 grams with all washers in the middle to hold rpm up. my gearing is also low 17/41 for MTX. This setup is a great crossover setup and is doing pretty well in the deep stuff. Under load when powder climing hill around 11,600-11,400 rpm and 11,800 rpm on hard pack at holeshot with clutch engaged. The 33LBS is engagement and the 211 LBS is total force good luck

 

[Ruggybuggy]

Your running a 41 helix? I have a 43 and works well with the green spring. Maybe a helix change. I was also running the pink but my RPM rose to 11,800 after I put my stock exhaust back on. I'm using Ulmers primary clutch kit, green spring, 17 tooth I the chain case, standard FX drives and spinning a 121 x 1.25 ripsaw track and now seeing 11,400 rpms at WOT.

 

[UP bushman]

I'm running 144" X 1.75 Back Country track with 41-34 multi angle helix.

 

[Ruggybuggy]

I'm running 144" X 1.75 Back Country track with 41-34 multi angle helix.

Where did you get the multi angle helix? I wouldn't mind experimenting.

 

[blueironranger]

KG per MM would be roughly 57# per inch compression. A stock Yami spring is a hair under 3" at 75mm in length. Going buy there free length measurements would make the Yami green spring a 37/86 and the sliver a 46/106 on there chart but who knows how accurate that is

 

[UP bushman]

Multi angle cut by Black Diamond Extreme in Minnesota. $80.00 includes helix & shipping US.

 

[MikeWalters]

KG per MM would be roughly 57# per inch compression. A stock Yami spring is a hair under 3" at 75mm in length. Going buy there free length measurements would make the Yami green spring a 37/86 and the sliver a 46/106 on there chart but who knows how accurate that is

Yes, that is the math I was looking for. Mind giving me your formula? How did you get the 2 values for the Yammi spring? (they only list one on the Yammi charts)

Thanks guys this is very helpful

 

[blueironranger]

actually comes out to 55.98 lbs. per inch

2.204 lbs per kg
25.4mm per inch
2.204x25.4 = 55.98 lbs per inch

Yamaha claims a stock spring is 75mm which is 2.95" long
The website your looking at gives weight ratings at 2.25 and 1.25 measured spring length (compressed)
So that gives us .70" and 1.70" compressed which we use as a multiplier.

Yamaha Green .87kg/mm
56#x 0.87 x .7 = 2.25" rating of 34#
56#x 0.87 x 1.7 = 1.25" rating of 83#

Yamaha Sliver 1.04kg/mm
56#x 1.04 x .7 = 41#
56#x 1.04 x 1.7 = 99#

Yamaha Pink
56#x 1.26 x .7 = 49#
56#x 1.26 x 1.7 = 120#

BUT we don't know how long the free length is on the springs from that aftermarket site and I #*$&@-u-me that there free length is probably longer since their 2.25" rating is higher that yami springs.

 

[MikeWalters]

actually comes out to 55.98 lbs. per inch

2.204 lbs per kg
25.4mm per inch
2.204x25.4 = 55.98 lbs per inch

Yamaha claims a stock spring is 75mm which is 2.95" long
The website your looking at gives weight ratings at 2.25 and 1.25 measured spring length (compressed)
So that gives us .70" and 1.70" compressed which we use as a multiplier.

Yamaha Green .87kg/mm
56#x 0.87 x .7 = 2.25" rating of 34#
56#x 0.87 x 1.7 = 1.25" rating of 83#

Yamaha Sliver 1.04kg/mm
56#x 1.04 x .7 = 41#
56#x 1.04 x 1.7 = 99#

Yamaha Pink
56#x 1.26 x .7 = 49#
56#x 1.26 x 1.7 = 120#

BUT we don't know how long the free length is on the springs from that aftermarket site and I #*$&@-u-me that there free length is probably longer since their 2.25" rating is higher that yami springs.

Great thanks. This is just what I need, just wanted a good starting point to get a similar spring. I have the green spring but yeah no idea how many miles on this clutch. My apex collar should be here today.

Thanks guys