Suspension Tech Thread

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Suspension Tech Thread
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flag chazdog
Posted: Feb 2, 2012 at 13:53 Quote
aceospades1250 wrote:
Here's an idea I had after seeing the new Ibis Ripley with the 2XC DW-Link

The problem is when you apply that idea to longer travel frames it gets harder to have a good leverage curve...so I added a shock linkage and came up with this:

photo

photo

It follows the typical DW-link axle path and anti-squat profile so I would think it would work pretty well.

now all you have to do is ask weagle reaaaaly nicely.....Dead Horse

is a good idea though Razz
flag cedric-eveleigh
O+
Posted: Feb 3, 2012 at 20:31 Quote
why is it good to have super soft early travel? wouldn't that worsen the pedaling efficiency?
the rest of the leverage curve I understand but I don't get the beginning of it..
flag aceospades1250
Posted: Feb 3, 2012 at 22:50 Quote
Look at the scale on the right side. It's actually fairly linear. The anti-squat maximizes efficiency, while the initial plushness maximizes wheel traction.
flag brigand
Posted: Feb 4, 2012 at 3:25 Quote
....and it goes more flat from the sag point on.... looks interesting
flag cedric-eveleigh
O+
Posted: Feb 4, 2012 at 5:24 Quote
but by the time you've gotten to the more linear part, you've already blown through 40 mm of travel. that's not what I call efficiency... I guess the dw bikes have a lot of chain stretch which makes up for it
flag brigand
Posted: Feb 4, 2012 at 5:32 Quote
40mm of travel is 25% sag (out of 160mm), i don't see a problem there
flag cedric-eveleigh
O+
Posted: Feb 4, 2012 at 5:54 Quote
pedaling efficiency is what I don't get. it's interesting how the bike would want to sit at it's sag point but it seems like the pedaling efficiency would get affected in a bad way
flag chazdog
Posted: Feb 4, 2012 at 5:59 Quote
antisquat curves need to eb seen to gauge the pedalling efficiency, its fairly independent of leverage (not totally, but is a more deciding parameter. Thats why the v10, with its 200% of antisquat though its entire travel pedals really well, despite its huge change in leverage through the stroke.
flag cedric-eveleigh
O+
Posted: Feb 5, 2012 at 17:07 Quote
are there any other advantages to the dw style S leverage curve?
it seems like it would create more inconsistency in the rear travel..
flag cedric-eveleigh
O+
Posted: Mar 6, 2012 at 17:53 Quote
when a company sais that their bike is fully active under braking and pedaling, what exactly are they implying? because I've heard that from companies that have a lot of brake squat and pedal feedback...
flag bansheeripper
Posted: Mar 7, 2012 at 12:33 Quote
cedrico wrote:
when a company sais that their bike is fully active under braking and pedaling, what exactly are they implying? because I've heard that from companies that have a lot of brake squat and pedal feedback...
"active under braking" means if you removed the shock, locked the rear brake, and applied forward rotational force to the wheel, that the suspension would not be inclined to move downward locking out suspension... " active under pedaling" means do the same things but apply chain tention(instead of rotational force) and the chain tention will not pull down on the suspension locking out suspension...
flag cedric-eveleigh
O+
Posted: Mar 7, 2012 at 13:13 Quote
banshee-ripper wrote:
cedrico wrote:
when a company sais that their bike is fully active under braking and pedaling, what exactly are they implying? because I've heard that from companies that have a lot of brake squat and pedal feedback...
"active under braking" means if you removed the shock, locked the rear brake, and applied forward rotational force to the wheel, that the suspension would not be inclined to move downward locking out suspension... " active under pedaling" means do the same things but apply chain tention(instead of rotational force) and the chain tention will not pull down on the suspension locking out suspension...

so a bike with some chain stretch or brake jack isn't 100 active under pedalling or braking
flag mozz
Posted: Mar 7, 2012 at 13:48 Quote
cedrico wrote:
banshee-ripper wrote:
cedrico wrote:
when a company sais that their bike is fully active under braking and pedaling, what exactly are they implying? because I've heard that from companies that have a lot of brake squat and pedal feedback...
"active under braking" means if you removed the shock, locked the rear brake, and applied forward rotational force to the wheel, that the suspension would not be inclined to move downward locking out suspension... " active under pedaling" means do the same things but apply chain tention(instead of rotational force) and the chain tention will not pull down on the suspension locking out suspension...

so a bike with some chain stretch or brake jack isn't 100 active under pedalling or braking

There are many factors that cause brake induced wheel movement, but i general the term active under braking relates to how much the wheel rotates due to the suspension relative to the ground For instance single pivots can have 10-15 degrees at full travel, where as treks ABP, and FSR are usually around 3 to 6 degrees. If you have zero the grip feed back from the rear wheel is very little and its hard to tell when you have locked the brake. Hence in "full active systems" they are not totally isolated.
flag mozz
Posted: Mar 29, 2012 at 23:08 Quote
BUMP. This thread is stagnant

After seeing this bike its got me thinking about re evaluating Unified Rear Triangles

Bicycle Fabrications Candyman single pivot steel 4X DS Dirt Jump bike featuring a Unified Rear Triangle.

As a single pivot and a URT at that . the bike has a pivot point optimized for a typical middle ring.

So lets discus the Judas of the suspension world the URT.
flag chazdog
Posted: Mar 30, 2012 at 3:26 Quote
the closest i'd consider is a pendbox or i drive style system where the cranks attatch to the rear and front trianlges. Unfortunately linkage has no provision for this really and its a pain to do the math

 


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