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Discussion Starter #1 (Edited)
Since new, I've been backing off the shock preload on my 07 after each ride thinking it would provide long term longevity benefits for both the spring and adjustment " system "

Probably an old school habit I've used for many years on various vehicles ( race cars etc. ) but not sure if there is any real benefit to this for the Vee.

My size requires 3/4 + preload for best all around feel but not sure backing it off after each ride is necessary. I will say the shock / spring still seem to be holding up just fine at 40,000 miles so maybe it has helped ??

Any thoughts appreciated.
 

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waste of time

Since new, I've been backing off the shock preload on my 07 after each ride thinking it would provide long term longevity benefits for both the spring and adjustment " system "

Probably an old school habit I've used for many years on various vehicles ( race cars etc. ) but not sure if there is any real benefit to this for the Vee.

My size requires 3/4 + preload for best all around feel but not sure backing it off after each ride is necessary.

Any thoughts appreciated.
nothing useful is achieved
 

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It sounds like you've never set the sag. I'm not familiar with "race" cars, but setting the sag on motorcycles is one of the first things I do. There are numerous threads about how to do this. Of course you can also find the procedure on youtube.
 

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Discussion Starter #5
It sounds like you've never set the sag. I'm not familiar with "race" cars, but setting the sag on motorcycles is one of the first things I do. There are numerous threads about how to do this. Of course you can also find the procedure on youtube.
Basically, I'm adjusting the " sag " and ride height each time I ride by the amount I compress or " pre-load " the spring.
 

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FORUM GODFATHER.....R.I.P. PAT
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You want about 40mm of suspension sag from full extension when the bike is carrying its designated load, including the rider. Unless that changes between rides, as in adding or subtracting luggage or a passenger, there is no reason to change the setting. You might want to "wiggle" the rear knob occasionally to keep the mechanism free but that's all it needs.
 

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Basically, I'm adjusting the " sag " and ride height each time I ride by the amount I compress or " pre-load " the spring.
Once the weight of the bike is on the suspension turning the preload knob has no affect on the spring compression. You're just raising or lowering the bike. Set your sag to 40mm and then leave it be.
 

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Putting the bike up on the center stand takes the load off the rear spring (and slightly increases the load on the front), but that's not what wears out. The mediocre damping of the rear gets more mediocre.
 

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Discussion Starter #9 (Edited)
The below paragraph is from the Progressive suspension website. The amount the spring is compressed by the amount of preload is what determines loaded ride height plus many other factors.

My original question was based on leaving the spring in a more compressed state ( via high preload setting per below paragraph ) I was just wondering if I would get longer, useful spring life by leaving it in an uncompressed state when not in use by backing off the preload ?

Look at two identical shocks, one with full preload, and one with no preload. The shock length is the same, its the overall length of the spring ( because one has been compressed ) that will be different.

Below is from Progressive site:

"This is where Preload Adjustment comes into play. By compressing or uncompressing the spring a small amount, a shock can be perfectly tuned to suit the conditions for which it will be used."

I'm thinking an analogy might be similar to why it is important to back off the preload to zero on a torque wrench when not in use.
 

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FORUM GODFATHER.....R.I.P. PAT
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That information about spring compression is only accurate if the wheel is off the ground or the suspension is topped out. If the wheel is on the ground and the spring is not topped out, changing the preload only changes the height of the bike. Don't worry about the spring. It's not going to take a set. Just set the preload so the bike loaded with the weight you will be carrying compresses the suspension about 40mm from full extension.

Just your getting off the bike is like lowering the setting on the torque wrench.
 

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Discussion Starter #11
Thanks G.W.

Think I'll just set it and forget it. :thumbup:

Thanks to all for your input.
 

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That information about spring compression is only accurate if the wheel is off the ground or the suspension is topped out. If the wheel is on the ground and the spring is not topped out, changing the preload only changes the height of the bike. Don't worry about the spring. It's not going to take a set. Just set the preload so the bike loaded with the weight you will be carrying compresses the suspension about 40mm from full extension.

Just your getting off the bike is like lowering the setting on the torque wrench.
Just for the benefit of anyone else reading this thread and who is not super suspension savvy, this info mentioned by greywolf (and the other posters) is vitally important. The term "preload", despite being used by the manufacturer, really is an awful one, as it creates the impression that it directly makes the suspension harder or softer when it doesn't ...

If you are not topped out (and you aren't with weight on the suspension) increasing or decreasing the "preload" only raises or lowers the ride height from within the suspension and doesn't change the "stiffness" of the spring.

On the (conventional) front forks that doesn't change the stiffness of the suspension. On the rear it can have a counter-intuitive effect. The rear linkage on almost all modern single shock bikes is set up to provide some degree of "rising rate". Lessening "preload" and thus lowering the suspension will move the swing arm up into a "stiffer" area of the linkage action and can result in a harsher feel to the rear end. The effect will vary depending on how each type of linkage is engineered.

This can also happen when adding loads such as a pillion and not compensating by increasing "preload" (ie add some ride height which is used up again by the spring compressing more under a greater load) to keep sag the same with this greater load, which may be where the term originated....

Of course, all of this is completely separate from issues resulting from changes to steering geometry arising from significant changes to sag settings.

FYI

chrs jc
 

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Discussion Starter #13
What exactly is changing when we add preload ? I realize the loaded ride height is increased ( the result ) , but what are we physically changing to give us the result of a change in ride height ? What mechanical change is occurring to the shock / spring ?
 

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FORUM GODFATHER.....R.I.P. PAT
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In the front it's a big screw pushing down on each spring. In the rear, it's a hydraulic piston pushing down on the spring. Since the force on each spring (weight of the bike) is unchanged, the frame rises.
 

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Exactly as GW said - there is no physical change to shock or spring, just the position of the top end of the spring is altered, up or down.

That's why I reckon the word "preload" gives the wrong idea...
 

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Discussion Starter #16
In the front it's a big screw pushing down on each spring. In the rear, it's a hydraulic piston pushing down on the spring. Since the force on each spring (weight of the bike) is unchanged, the frame rises.
Thats been my understanding.

And as such. doesn't a coil spring, the more it is compressed, require progressively more and more load to compress further ?

Isn't this what allows us to carry more weight and maintain the desired ride height by adding more and more initial spring compression because it now take greater force ( weight ) to further compress it ?

Wouldn't this mean we maintain greater ride height because the spring is no longer compressing as easily ?

Thanks for the input GW. ( not trying to argue, just trying to understand :yesnod:
 

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FORUM GODFATHER.....R.I.P. PAT
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Dialing in more preload does not compress the spring unless it is topped out. It won't be if set properly. You are not changing the spring compression.

Think of yourself standing on a spring. Then take a one inch block of wood out of your pocket and put it on the spring and stand on it. You are one inch higher and the spring is compressed the same amount as it was without the wood.
 

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Discussion Starter #18
I've got to study this more !! :yesnod:

Thanks for the replys and conversation.
 

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The only thing that compresses the spring (bike stationary) is weight. Same weight, same compression...
 

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I've got to study this more !! :yesnod:

Thanks for the replys and conversation.
This may help a little:

SonicSprings.com

The longer post by Zone5 is an excellent summary of what's going on. I like Pat's block of wood example too, I may steal that. :)

On your original concern about the spring fatiguing, that's really not an issue anymore. There was a time when OEM springs where made out of alloys not really up to the task, and they would derate over time. Now the quality is better, the only problem is that the rate is still usually too soft to start with. :)
 
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