Whats the difference between linear and progressive suspension designs?

PB Forum :: Mechanics' Lounge
Whats the difference between linear and progressive suspension designs?
  • Previous Page
  • Next Page
Author Message
flag nickbedell83
Posted: Apr 2, 2008 at 9:10 Quote
I am about half educated on this.

someone please explain for this one agian for me.
flag longride
Posted: Apr 2, 2008 at 10:48 Quote
All suspension systems resist compression more towards the bottom of the stroke (reaching full compression) than they do at the beginning of the stroke (when they are not compressed).

Linear and non-linear suspension differ in the rate at which the resistence increases.

Linear suspension will increase resistence at a steady pace. Hypothetical Example: For every 10 cm of shock compression the effort required to compress the shock will increase by 100 Newtons, regardless of how compressed the shock is.

With Non-Linear ("progressive") suspension the amount of effort does not increase at a steady pace- instead it increases slowly at the beginning of the stroke, and much more rapidly near the bottom of the stroke. Using the last example: the effort required to compress the shock through the 1st 10cm may only by 50 Newtons, but the effort required to compress the shock through the last 10cm may be 300 Newtons. It gets progressively harder to compress the shock- thus the name.

Another example:

Compression......Linear Effort............Progressive Effort
---------------------------------------------------
10 cm.......... 100 (100 Total)............. 50 (50 Total)
20 cm ......... 100 (200 Total)............ 100 (150 Total)
30 cm ......... 100 (300 Total)............ 150 (300 Total)
40 cm ......... 100 (400 Total)............ 200 (500 Total)
... ... ...
flag reallybigmantis
Posted: Apr 2, 2008 at 10:57 Quote
if you paid attention in math class you would recognize progressive as an "exponential curve", whereas linear is a constant curve.
flag nickbedell83
Posted: Apr 2, 2008 at 11:20 Quote
reallybigmantis wrote:
if you paid attention in math class you would recognize progressive as an "exponential curve", whereas linear is a constant curve.


obviously i did not pay attention in math class...
flag SpikeX
Posted: Apr 9, 2008 at 8:24 Quote
Coil-type forks and shocks have more of a linear travel curve (which is why a lot of people still go with coil suspension), whereas air forks and shocks have a progressive curve.

My RockShox Reba SL 100mm air fork has a very progressive curve. At the very beginning of the travel, it performs great and absorbs all the bumps, then after that stage it blows through all the travel, and at the final stage it's impossible to compress any further and you can't really bottom it out (because it becomes so hard to compress in the last 1-2cm of travel that I can't bottom it out at all).
flag anguswyatt
Posted: Nov 7, 2012 at 9:05 Quote
nickbedell83 wrote:
reallybigmantis wrote:
if you paid attention in math class you would recognize progressive as an "exponential curve", whereas linear is a constant curve.


obviously i did not pay attention in math class...

the progressive will be an exponential curve while the linear will be a straight line. Good try though.
flag MaxAlary
Posted: Nov 7, 2012 at 9:54 Quote
anguswyatt wrote:
nickbedell83 wrote:
reallybigmantis wrote:
if you paid attention in math class you would recognize progressive as an "exponential curve", whereas linear is a constant curve.


obviously i did not pay attention in math class...

the progressive will be an exponential curve while the linear will be a straight line. Good try though.

That's exactly what he said . In math the "curve" of a function doesn't actually need to be a curve, it's more of a notation of a funtion represented on a graph. So both of you were right.
flag jooseygoose
Posted: Nov 7, 2012 at 12:40 Quote
MaxAlary wrote:
anguswyatt wrote:
nickbedell83 wrote:



obviously i did not pay attention in math class...

the progressive will be an exponential curve while the linear will be a straight line. Good try though.

That's exactly what he said . In math the "curve" of a function doesn't actually need to be a curve, it's more of a notation of a funtion represented on a graph. So both of you were right.

This is the last place I though mathmatic symantics would be argued, but looks like I am wrong.
flag alexcm0110
O+
Posted: Feb 27, 2018 at 14:27 Quote
Lol. From the series "How would a brit, an american and a canadian argue over a straight line..."
  • Previous Page
  • Next Page

 


Copyright © 2000 - 2024. Pinkbike.com. All rights reserved.
dv56 0.012052
Mobile Version of Website