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Look very carefully professors, and choose your next bike.
Did anything surprise you?
Mountain Bike Suspension Systems
What a strange idea. Do something "for science" and yet include no scientific
data or measurements of any sort.
Here are some scientific approaches to this:
Use a measuring tape from the center of the rear axle to the center of the BB.
This will show chain growth or shrinkage through the travel. Note that some
linkage type suspension designs
Use a piston to slowly apply pressure downwards at a fixed rate of movement.
Place a scale or sensor against the piston. Observe and chart the changes in
pressure as the piston keeps a constant speed. This will show the
progressiveness of the compression stroke.
Lock out your rear suspension. Place 100kg of weight on the saddle. Observe
compression. Increase to 200kg, observe. Increase to 300kg, observe. Now
remove 200kg and slowly add the weight for one second and take one second to
remove the weight. This will mimic pedaling under high load by a strong rider
on rough terrain riding uphill. Now openly mock people who believe that
pedaling platforms are better than real lockouts, because "science".
Also, there are 17 brands of full and bikes here, but there aren't 17
suspension systems. When considering chain growth, there are only 4. Single
pivot, BB pivot, vpp and etsx (aka maestro after it was shamelessly ripped off
by Giant). Single pivot shrinks chain under compression. Horst and other 4
bars too. BB pivot is not used by anyone anymore, not even Wal-Mart, but the
chain does not grow. VPP has an S shape, usually shrinking, then lengthening,
usually with th changeover occurring at the sag point. And etsx grows the
chain under compression. Maestro is a ripping of etsx, so it also grows, but
they linkages are much shorter, so the chain growth is minimal.
If your chain shrinks under compression, your pedaling travel will be lost
into your drivetrain and be returned to your bikes position when the pedaling
force subsides. If your chain grows under compression, the chain growth will
drive your rear wheel against the ground, returning against no resistance and
putting the slack possibly against the freewheel like a ratcheting effect… If
you have low enough engagement points or a silent clutch instant engagement
If there are two pivots between the fixed point on the bike and the center of
the rear axle (not AT the rear axle), then your bike is not a single pivot.
Even if you have fancy linkage up top, but one pivot on the chain stay, that's
still a single pivot in terms of chain growth.
Beyond that, linkages can affect how progressive your suspension travel is.
On my perp for example, it has some linkage to make it more progressive, so
even a lower grade shock provides progressive travel if it is sprung
correctly. But don't confuse that with aggressiveness in the shock itself,
which can also be an important factor in real world use.
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I wish they had the Ibis Ripley…I am curious how that thing cycles through
with the two cams.
So what's the answer???
They missed GT with idrive or AOS which would have shown the least chain
growth of all of them and yeti SB66 which is 2nd.
This seems like an exercise in onanism and with little no informative value.
Gives you some perspective on chain growth for various suspension platforms…
other than that its not really that useful…
VPP's look like falling rate at the end stroke.
its actually rising rate at the end
The Fox DYAD?
They all have the same movement. Is there a real difference?
I was hoping the video will use the first song.
Because I often go full rear travel without budging my fork…. useless video.
No kidding. Compressing with weight on the pedals and handlebars would be much
And why were some drive trains in 1st gear and others in 4th or higher?
Consistent configurations would be good.