Linkage design blog...
 

[Closed] Linkage design blog...

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Maybe I'm a bit too geeky but I really enjoy looking at the analysis on there.

However, has anyone noticed that the last chart, the trace always looks the same?


 
Posted : 03/02/2017 9:33 pm
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I used to think that but it's only in the last few days that I've realised the significance of it - mostly because I've now got a Luftkappe in my fork and I was trying to see how the spring curve compares on the frame+shock.

The last chart shows the force vs travel at the rear wheel (that's the curve going from low to high, left to right) and also the rate of change of this spring rate at the wheel.

How high the spring rate goes shows you the bottom-out force (ignoring damping) whilst how low the rate of change of spring rate is at the start shows you how sensitive the bike will be to small bumps (and how much grip it has), and how high that rate of change stays in the mid-stroke shows you how resistant the bike is to wallowing/falling through the travel.


 
Posted : 03/02/2017 10:37 pm
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Sorry, I guess what I should have said was give how much bikes can very, it's surprising just how similar the shape of the final spring curves actually are.


 
Posted : 03/02/2017 11:35 pm
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Yes but the rate of change plot varies more - and apparently the way we perceive the spring rate is as a squared function of the graph, so differences are massively accentuated.


 
Posted : 03/02/2017 11:49 pm
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That's interesting about the perception being squared. Where is that from?

I'm sad enough to be interested in this stuff but half the battle can be sorting the wheat from the chaff.


 
Posted : 04/02/2017 8:04 am