Progressive suspension springs, how to mount?


Information and questions on GL1200 Goldwings (1984-1987)
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Kripestam
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GL1200 -84

Progressive suspension springs, how to mount?

Post by Kripestam »



Hi!
Fast question.. which direction should I mount the springs?
Gl1200-84 aspencade air shocks.
/Klas
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WingAdmin
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Re: Progressive suspension springs, how to mount?

Post by WingAdmin »

Conventional wisdom has had the tighter coils at the bottom, as they compress before the more loosely wound coils, that way on small bumps you have less mass of the spring being actuated when absorbing those bumps (and less kinetic rebound energy that would have to be damped).

In reality, you would probably not notice much if any difference either way you install it. I'd still do it tight coil end down though if it were my bike.

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CrystalPistol
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Re: Progressive suspension springs, how to mount?

Post by CrystalPistol »

The spring doesn't care, a same weight will compress it the same per coil either way up. With Fork springs, they recommend to put close coils in bottom simply to immerse them in oil, to isolate their coil contact noise away from rider's ears. They will compress the same either way up as well. With the springs in the picture, same seat type on both ends, either way is A-OK.

If you have a coil spring with 10 coils and a 150 pound per inch rate, 150 ponds will compress that spring total 1 inch, or 1/10th inch each coil. If 3 coils are closer together, they stack up first obviously, but the remaining 7 coils still can resist another 150 pounds per 1/10th inch individually, but there's fewer of them, so that 150 pounds only compresses the spring's remaining coils 7 X 0.10" or 0.70" as the three are still stacked, that's a higher rate than the 150 lbs per 1.00 inch of spring rate when all coils could compress.

That's why progressive rate springs have tighter wound coils on one end. Steady rate springs usually have same coil spacing. It's easier that tapering spring wire to make / control.
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oldmopars
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Re: Progressive suspension springs, how to mount?

Post by oldmopars »

I will chime in with a "What they said".
It just does not matter what way you put them in, wide coils up or down, you will never notice any difference. However, what ever you decide, just do it the same on both sides. It would not matter performance wise, but people with OCD will care. :D



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