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Old 08-28-2020, 02:58 PM   #16
m0t0_ryder
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Although it could be minimal you will probably cause more degradation to the fork springs by holding them (near full) compressed for periods of time than to the fork seals for reasons mentioned above.

Springs, in general, are not meant to be compressed for extended periods of time.

HERE's some info.

snip...
Quote:
Does Leaving a Spring Compressed Weaken It?
A spring under tension for an extended period of time can become weaker. Any object will either resist or deform when subjected to outside stress. Springs are specifically designed to deform in order to absorb energy from outside stress, then return to their natural state when they release that energy.

FATIGUE
Over a long enough period of time, fatigue can occur, which is a condition where enough stress has repeatedly acted on the object and some deformation becomes permanent. In this case, it is harder to regain its complete normal shape. This is essentially what happens when a spring wears out. If the spring is well-constructed, then under normal circumstances, you should go through many cycles of compression or release over many years before fatigue occurs.

CREEP
Creep is another phenomenon that may affect a spring under tension. Creep refers to when an object is exposed to a compressing structural load that creates a high level of stress that is less than the yield strength of the material. Creep is more often seen when the spring is subjected to high levels of heat for a long period of time, but it can happen anytime extended stress occurs.

As a result of creep, the spring deforms as normal but cannot regain its complete normal shape, essentially accelerating the effects of fatigue. If enough creep occurs, the spring may deform so much that it is unable to collect sufficient potential energy to do its job. As a result, the spring is weakened, sometimes even to the point where it does not function at all and must be replaced.
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Old 08-28-2020, 07:03 PM   #17
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Old 08-28-2020, 07:15 PM   #18
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Old 08-29-2020, 10:32 AM   #19
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Originally Posted by m0t0_ryder View Post
Although it could be minimal you will probably cause more degradation to the fork springs by holding them (near full) compressed for periods of time than to the fork seals for reasons mentioned above.

Springs, in general, are not meant to be compressed for extended periods of time.

HERE's some info.

snip...
Leaving a spring compressed does not weaken it. Unless you stack the coils in which case it will reduce the overall height of the spring just a little. Sometimes. And usually proper spring design accounts for this.

Facts is, a properly designed spring will not be weakened by holding it compressed. It's a fairy tale. And the same with cycling a spring. As long as you don't go to a fully stacked state all the time, the life of the spring is almost indefinite. Another fairy tale.
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Old 08-29-2020, 11:41 AM   #20
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You don't want to compress and hold any spring to the degree where the coils bottom...

Many Japanese fork and shock springs still employ piano wire or music wire which
is not fatigue resistant as Chrome silicon steel found in after market springs such as Ohlins...

Spring material is why some stock springs grow weak and sag over time whereas
quality after market springs don't...
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