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Discussion Starter · #1 ·
I've been researching spring rates and according to the charts I've seen. The lower the opening angle the lower the spring rate.

But I've read over and over again that the lower the opening angle the stiffer the spring. What gives?
 

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Discussion Starter · #2 ·
Ok let me ask this. What spring is stiffer a 10.4 with a 75 degree opening angle or a 10.4 with 85 degree?
 

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Not my area but would guess the 85 is going to be loaded up more than the 75 so, the 85 will be stiffer.
 

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Discussion Starter · #5 ·
Thanks for the chart but I've looked at plenty. That's my point according to the charts the lower the opening angle the lower the spring tension.

But I've read posts from guys like Tweener that know their stuff and they say the heavier the rider the lower the opening angle!!!!! What am I not

understanding????I'm trying to find the lowest tension spring that fits a SC10-II.
 

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Discussion Starter · #8 ·
Not my area but would guess the 85 is going to be loaded up more than the 75 so, the 85 will be stiffer.
I would theorize that too, but according to a most people I've talked to its the other way around!!

Although it wasn't explained to me why! So can anybody explain this in easy to understand terms?

So the softest spring I can find for my strapped down SC10-II is the smallest wire diameter with the

largest angle opening? How do you measure the opening angle?
 

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I would theorize that too, but according to a most people I've talked to its the other way around!!

Although it wasn't explained to me why! So can anybody explain this in easy to understand terms?

So the softest spring I can find for my strapped down SC10-II is the smallest wire diameter with the

largest angle opening? How do you measure the opening angle?
Got it. I'm listening and hoping to learn something here. Pretty sure "angle of opening" references torsion springs only.

Edit: So I spent some time reading the t-spring charts and it appears the wider the opening angle the stiffer the spring as suspected. For instance, in one of my applications, the soft right t-spring is 191-612 with an opening angle of 95. The stiff right t-spring is 191--614 with an opening of 100.

That holds true with 2 others I've checked.

I would think you could put your springs in a vise, heat with propane torch and bend the long leg to close the angle to 50 deg or so. This would surely allow for more sag.
 

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When you consider what happens with the spring when the suspension compresses, it will make sense. The spring flattens out more as the suspension compresses. So if two springs were made from identical material, the one with the lesser angle opening would be a stiffer spring as it is going to have to be preloaded more to install. Hope this helps.
 

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Less opening angle means the ends are closer together. Remember the short spring end is on the back side of the adjuster block. As you turn the block so the thicker settings are touching the spring, it increases the preload and makes the spring stiffer. Same thing applies to the opening angle. If the spring ends are closer together, the spring needs to be wound more before it flattens out under full compression of the suspension. So the closer the spring ends are together, the more force that will be required to fully compress that spring.
 

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Discussion Starter · #12 ·
Ok got it!! The charts are deceiving in listing lower spring rates at a lower opening angle. Now what springs will all fit in the SC10-II

and where can I find some more charts that include the spring rates? If I can't bend my springs enough I'll be looking for the lowest

spring rate I can find. " Smallest wire diameter with the largest opening angle". I found a spring in my 98 race manual 486 0786 00

that is recommended for a lowered SC10. Don't know if it will fit mine or if their even available anymore. Maybe a 01 or 02 race manual

lists one for the SC10 II.
 
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