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Liked a comment about photo 2016 M16 Carbon at Eurobike 8/26/2015 10:57 AM
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After many years of development they have arrived at the santa cruz v-10

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Liked a comment about video Vital RAW - Val di Sole World Cup DH Mega Banger 8/20/2015 4:42 PM
C138x104

all of them

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This video has 17 comments.

Liked a comment about slideshow A Tribute to Will Olson - Memorial Ride, Enduro World Series, Crested Butte 8/4/2015 10:35 AM
C138_willa

Oh my goodness... Lee Trumpore, Eddie Clark - THANK YOU, THANK YOU, THANK YOU for doing this. This is so incredibly beautiful, thoughtful, amazing. Will would be blown away. Thank you for honoring my boy in this way... He loved you guys - this whole community. Peace and love, Will Olson's girlfriend, Bonnie

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This slideshow has 14 comments.

Liked a comment about video Desk to DH: From Cube Life to Race Tape in Eight Days 7/9/2015 9:33 AM
C138x104

awesome video i find myself being the same boat turning 30 this year and having a ton of fun racing enduro in my hometown, around my province and even in new zealand cheers to you Jeff!

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Liked a comment about video Desk to DH: From Cube Life to Race Tape in Eight Days 7/9/2015 8:27 AM
C138x104

Definitely doesn't warrant its own post. On pinkbike they do way more fascinating things like ride some average trail bike that "inspires confidence" and is "just as capable as a dh bike". That's much more legit as stand alone content.

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Liked a comment about slideshow How To Get The Most Out Of Your RockShox Suspension 6/19/2015 10:22 PM
C138_rockshox_spota

I'm impressed by your enthusiasm.

Re-read my comment with the graph. I don't disagree with you about how a volume change at the same starting pressure will alter the spring rate.

However, the slope (aka spring rate) does indeed change when you up the air pressure. Let's do some very basic math, using the nice orange and red dots at the 2-inch travel mark on the 4-inch chamber lines as an easy reference point.

Rise / Run = Slope

The 4-inch chamber with 200psi rises from 200lbs at 0-inches to 400lbs at 2-inches.
The 4-inch chamber with 100psi rises from 100lbs at 0-inches to 200lbs at 2-inches.

400lbs - 200lbs = 200lbs
200lbs - 100lbs = 100lbs

200lbs (rise) / 2in (run) = 100lbs/in
100lbs (rise) / 2in (run) = 50lbs/in

While they may look "more or less parallel," they're far from it.

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Liked a comment about slideshow How To Get The Most Out Of Your RockShox Suspension 6/19/2015 9:41 PM
C138_rockshox_spota

kc358, you've got some wires crossed. Changing air pressure does indeed change the spring rate. Here's a graph from RockShox to illustrate this fact:



Spring rate describes the stiffness of a spring and is defined as the (change in force) / (change in displacement). It's usually measured in lbs/in - the pounds of force necessary to compress the spring by one inch. In the graph, note the red and orange lines that represent different pressures in the same volume. In the case of the 100psi red line, we see a change in force of 100lb over 2-inches. The 200psi orange line sees a change of 200lb in those same 2-inches. If the spring rate did not increase as you increase pressure, the change in force over those 2-inches would be the same.

As you noted, almost all air springs have a progressive spring rate, which means that they get stiffer the more they are compressed. As you also noted, yes, changing the volume also increases the spring rate (note the red and blue lines and their respective 100lb increase vs ~200lb increase over 2-inches) - this is why many riders will reduce air pressure by a few psi as they add more Tokens in order to keep a similar sag level and initial stroke feel.

Yes, the force necessary to initially compress the air spring due to the static pressure (breakaway force) also increases as you up the pressure, but RockShox offsets this with their auto-adjusting SoloAir negative spring, The effect of the negative spring isn't shown in this graph, but the breakaway force is reduced by the amount of force created by the negative spring pressure.

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Liked a comment about news blog RESULTS - Leogang World Cup Downhill Final 6/14/2015 8:52 AM
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Courtesy of Uncle Cliffy.

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