Looking at a shock with a digressive rebound stack. Why would I want or not want this? Shock would go on a trail bike with 2.8-2.35 relatively progressive curve that flattens at the end.
Help me understand digressive rebound
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first you're going to have to describe what digressive means
and then point me to this product so I can laugh at it
(you don't want it, unless you're talking a really flat curve at the end of travel and not an airshock)
and then point me to this product so I can laugh at it
(you don't want it, unless you're talking a really flat curve at the end of travel and not an airshock)
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The rebound shim stack is preloaded.
It will be stiffer initially at low forces, then "softer" (relatively) ay higher forces.
Some claim it's good for "pop", and it is often used in XC tunes.
Not a fan.
It will be stiffer initially at low forces, then "softer" (relatively) ay higher forces.
Some claim it's good for "pop", and it is often used in XC tunes.
Not a fan.
which is exactly what already happens with every other shim stack since they're inherently speed sensitive.
It would be the opposite, rebound speed would be slower as spring force drops.
Yes, but look at the pretty colored lines.
now do one from a dyno and not a philosophy book
A digressive (preloaded) shim stack takes more force to open initially than one that is not preloaded.
sure but every needle adjusted rebound stack is preloaded
No, not true at all.
Every rebound stack can be preloaded as a tuning option, same as the compression stack.
But they are not inherently preloaded.
But they are not inherently preloaded.
okay, every rebound stack is preloaded
I know, not like a base valve or most midvalves with float but there's really not that much difference. Forcing the return port is avoiding rebound damping, not using it. No ground irregularities are that regular in mtb. I could see it in SX whoops but not much else.
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who's selling this?
please show me, I'm serious
I hope they have explanations as good as rockshocks with rapid recovery. This was revolutionary.
look at that pump track....just LOOK at it!
you can SEE the recovery being more rapider
please show me, I'm serious
I hope they have explanations as good as rockshocks with rapid recovery. This was revolutionary.
look at that pump track....just LOOK at it!
you can SEE the recovery being more rapider
whoa
rapid recovery.......take a seat son
rapid recovery.......take a seat son
In all seriousness, anybody remember the first gen dhx2s and why they sucked so bad? Extremely low amounts of high speed rebound damping. I actually got steve at vorsprung to put a ginormous preload spacer in one that essentially locked it out (not the same as preloaded because it didn't move). That was a velocity problem, this is a force one, but the effect is similar. If you really want to get bucked off a progressive suspension design (which you should be riding on) this is the way to go.
I have a pair of '23 Super Deluxe air shocks - one has the stock/generic light compression / linear rebound tune, and one has an OEM tune for a Specialized SJ Evo with progressive rebound / light compression. The way it was explained to me was the progressive rebound is more open/faster on the smaller/faster compressions, and slower/more closed on bigger/faster compressions.
On the bike with the PR tune, it does seem to be a bit quicker on little chatter, and I don't have to run it as far open to create a good feel. But it's a bit harder for me to wrap my head around the rebound feel when tuning compared to the linear rebound tuned shock.
On the bike with the PR tune, it does seem to be a bit quicker on little chatter, and I don't have to run it as far open to create a good feel. But it's a bit harder for me to wrap my head around the rebound feel when tuning compared to the linear rebound tuned shock.
Because they puked oil on the second run out of the box?
the other reason
Nostalgia
Sometimes the preload is used to keep the valve closed and prevent float. This tends to make it react better to direction changes, but then RS takes it too far and the damn thing basically never even opens. Or Fox ****s up the rebound flow with a piston that can't flow high speed enough (Bomber CR), etc.
Sounds like it needs moar shimz. Or perhaps different valve geometry.
there is no better digressive damping than hysteresis
look how dynamically digressive this is
there is no better digressive damping than hysteresis
look how dynamically digressive this is
I wasn't sure if that was cavitation or just the back of your paper table mat when someone gave you some crayons.
More of a Uhaul guy.
ah yes
uhaul shocks
world renowned
just fyi I'm talking about suspension components not sticker shocks from hidden rental fees
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mmmm ok. Patient is a fox DPX2:
Description: 2018, FLOAT DPX2, P-Se, A, 3pos-Adj Evol LV, Pivot, Shuttle, 7.875, 2.0, 0.6 Spacer, CM, DRM, Rezi A F M, No Logo
"DRM" means digressive rebound, medium, as I understand it.
This is the patient, though the last 15mm or so are lopped off due to a short stroke on the shock
I think this is the bike the shock came off of:
It looks like it should work, although I may need additional air can spacers. I mostly want to know if it will work and if it will work well. I realized I don't really know what a digressive rebound tune actually means out on the trail, so I'm asking you homeboys.
Description: 2018, FLOAT DPX2, P-Se, A, 3pos-Adj Evol LV, Pivot, Shuttle, 7.875, 2.0, 0.6 Spacer, CM, DRM, Rezi A F M, No Logo
"DRM" means digressive rebound, medium, as I understand it.
This is the patient, though the last 15mm or so are lopped off due to a short stroke on the shock
I think this is the bike the shock came off of:
It looks like it should work, although I may need additional air can spacers. I mostly want to know if it will work and if it will work well. I realized I don't really know what a digressive rebound tune actually means out on the trail, so I'm asking you homeboys.
Rockshox used to be a big fan of digressive rebound stacks, as shown by their 'rapid recovery' marketing. It went so far as shown here by SteveM that some rebound stacks were so preloaded, they basically never opened.
When you compare a digressive rebound stack with a linear one, and tune them for parking-lot-feel, It will end up being overdamped on midsized impacts (roots), while underdamped on big hits and compressions. The argument can be made that it will feel more 'stable' over pumpy trails, while allowing fast rebound on big holes.
I recently went from an XC bike with Monarch (with rapid recovery) to a bike with a Deluxe (similar pistons, more linear rebound), and it feels a lot more poppy over jumps, and more predictable on rough terrain, but for each their own.
I think the change in frame leverage ratio will have a bigger impact in feel than the way they achieved their rebound damping. You are going from a shock damped for a rate of ~2.6 to a 2.35. If you are on the heavier side, and have to ride high pressure, this might actually be benefitial.
When you compare a digressive rebound stack with a linear one, and tune them for parking-lot-feel, It will end up being overdamped on midsized impacts (roots), while underdamped on big hits and compressions. The argument can be made that it will feel more 'stable' over pumpy trails, while allowing fast rebound on big holes.
I recently went from an XC bike with Monarch (with rapid recovery) to a bike with a Deluxe (similar pistons, more linear rebound), and it feels a lot more poppy over jumps, and more predictable on rough terrain, but for each their own.
I think the change in frame leverage ratio will have a bigger impact in feel than the way they achieved their rebound damping. You are going from a shock damped for a rate of ~2.6 to a 2.35. If you are on the heavier side, and have to ride high pressure, this might actually be benefitial.