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Question on using compression instead of rebound adjustments

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There are some videos on line I found and think the person that made them are on here but the videos take place at a ktm dealer and there are 3 of them.

Anyways in the second video it talks about your back end jumping or kicking or pogoing and I know the first thing everyone says on here is slow down the rebound, but in the video the guy said to try to tune more things out using the compression and if I understood correct you want to run the fastest rebound possible and softer. Compression also?

Can anyone explain this more to me like if your bike is skipping across bumps how do you use the compression for this or any example works

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If you're talking about square edge bumps (small, peaky, close bumps), you want your compression set at a soft setting so the suspension can soak them up. You also want your rebound set at a soft (fast) setting. By doing so, you ensure that your suspension will stretch out completely before the next bump, keeping your wheel in contact with the ground at all times.

If your rebound isn't fast enough, your suspension will be stuck at the end of its stroke after a few bumps only, making it feel harsh and stiff, and you will lose contact with the ground between them.

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There are some videos on line I found and think the person that made them are on here but the videos take place at a ktm dealer and there are 3 of them.

Anyways in the second video it talks about your back end jumping or kicking or pogoing and I know the first thing everyone says on here is slow down the rebound, but in the video the guy said to try to tune more things out using the compression and if I understood correct you want to run the fastest rebound possible and softer. Compression also?

Can anyone explain this more to me like if your bike is skipping across bumps how do you use the compression for this or any example works

I like to use comp. to dial out the harshness. When you open the comp.clickers you are increasing bleed/flow around the shim stack thus making a softer fork in return you get a plusher feel at he bars.

MX applications IMO, your rebound will only take you so far before anything else will affected. Ex. when you land from a jump landing and your front end bounces up? You have too fast of rebound. But then you say, its harsh over bumps. You know if you make rebound faster on the front that you will bounce, so you go to the compression and loosen or turn out the adjustor.

You can use both to dial out the harshness, it just depends on the situations.

hope this helps.

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the thing you have to remember is that the rebound adjuster has a large impact on compression also. I don't think rebound is a good name for it, forks it should be mid valve bleed and shock its the main bleed. Compression in forks only controls compression bleed in the base valve. In the shock the compression adjuster controls bleed into the bladder area caused by the shock shaft displacing oil in the shock body. Rebound adjuster in the shock controls bleed both directions around the shims.

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the thing you have to remember is that the rebound adjuster has a large impact on compression also. I don't think rebound is a good name for it, forks it should be mid valve bleed and shock its the main bleed. Compression in forks only controls compression bleed in the base valve. In the shock the compression adjuster controls bleed into the bladder area caused by the shock shaft displacing oil in the shock body. Rebound adjuster in the shock controls bleed both directions around the shims.

This is huge. This is a great way to show how this stuff works.

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sdjclevland, Comp damping converts wheel impact kinetic energy into heat. If you are too soft on the comp damping, then your spring(s) stores more energy by going further into the stroke, which is released during the rebound. For this reason softer comp damping does not always mean smoother more level ride.

With reb and comp, you have to find the sweet spot for best traction and control. It is not always easy to decide if the low speed or high speed comp needs adjustment.

As the others wrote, change both.

If in doubt I like to go as fast as possible on the reb, and as slow (firm) as possible on the comp, to stay high in the stroke.

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the thing you have to remember is that the rebound adjuster has a large impact on compression also. I don't think rebound is a good name for it, forks it should be mid valve bleed and shock its the main bleed. Compression in forks only controls compression bleed in the base valve. In the shock the compression adjuster controls bleed into the bladder area caused by the shock shaft displacing oil in the shock body. Rebound adjuster in the shock controls bleed both directions around the shims.

this is 100% correct. but I have to add that rebound stacks are much stiffer than compression stacks, so the bleed has more effect on rebound (thats why its called rebound clicker).

for those who can hardly imagine why, I always go to extremes when I think about somthing.

if you have almost no resistance (soft stack, here compression) it doesn't help a lot to add a bleed. that's the reason the compression cklicker has no influence on rebound. the checkvalve is open at rebound so it doesn't help to add a bleed here

if you have a big resistance, big pressure buildup, a bleed will much more drop this pressure, so a bigger influence...

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I see you're point, but you are mixing different parts of the suspension. When you say soft stack for compression I assume you are talking about the mid valve and then you say check valve which is in the base valve. You're point is valid to some extent but not totally accurate. In the base valve, the compression adjuster doesn't affect the rebound because the low speed shims block reverse flow through the compression adjuster. And for the mid valve with the soft compression stack, opening the rebound adjuster and letting more bleed has a simliar effect to increasing float. A good example is to try to bleed your shock with the rebound adjuster turned all the way in, it's much harder to compress the shock because the rebound adjuster has a great influence on compression

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In the base valve, the compression adjuster doesn't affect the rebound because the low speed shims block reverse flow through the compression adjuster. And for the mid valve with the soft compression stack, opening the rebound adjuster and letting more bleed has a simliar effect to increasing float.

believe me, i don't mix different parts...

there are some BV with bleed stacks, but there are also BV without bleed stacks. if the checkvalve is open, there is nearly no effect in adding bleed to an open port.

and I didn't say the rebound clicker has no effect on compression.

I said it has more effect on rebound than on compression. so yes, it does add a small amount to the relative big opening of the float, but it will affect rebound more...

as for the shock, compressing it by hand is ultra low speed. and, due to the wheel/shock ratio, a shock is much stiffer. so with a completely closed rebound clicker you cannot compress it. but installed in the bike the ratio will allow you easely to compress the shock because the shims open.

but its true, on shocks the rebound clicker has relatively more effect on compression damping than it has on forks

Edited by kawamaha

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the thing you have to remember is that the rebound adjuster has a large impact on compression also. I don't think rebound is a good name for it, forks it should be mid valve bleed and shock its the main bleed. Compression in forks only controls compression bleed in the base valve. In the shock the compression adjuster controls bleed into the bladder area caused by the shock shaft displacing oil in the shock body. Rebound adjuster in the shock controls bleed both directions around the shims.

:busted::worthy::busted:

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There are some videos on line I found and think the person that made them are on here but the videos take place at a ktm dealer and there are 3 of them.

Anyways in the second video it talks about your back end jumping or kicking or pogoing and I know the first thing everyone says on here is slow down the rebound, but in the video the guy said to try to tune more things out using the compression and if I understood correct you want to run the fastest rebound possible and softer. Compression also?

Can anyone explain this more to me like if your bike is skipping across bumps how do you use the compression for this or any example works

So I reread your post and you are referring to the shock not the front.:busted:

I guess it was too early.

So like the others say, the rebound can be used to dial out the harshness in

the shock. I run my rebound kind of quick and makes for a plusher feel.

And rebound does affect compression as well. Next time you have your shock of the bike, take the spring off and turn in the rebound all the way and you will see how it affect compression.

Sorry for the confusion:thumbsup:

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the thing you have to remember is that the rebound adjuster has a large impact on compression also. I don't think rebound is a good name for it, forks it should be mid valve bleed and shock its the main bleed. Compression in forks only controls compression bleed in the base valve. In the shock the compression adjuster controls bleed into the bladder area caused by the shock shaft displacing oil in the shock body. Rebound adjuster in the shock controls bleed both directions around the shims.

:busted: Good post jjy!

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the thing you have to remember is that the rebound adjuster has a large impact on compression also. I don't think rebound is a good name for it, forks it should be mid valve bleed and shock its the main bleed. Compression in forks only controls compression bleed in the base valve. In the shock the compression adjuster controls bleed into the bladder area caused by the shock shaft displacing oil in the shock body. Rebound adjuster in the shock controls bleed both directions around the shims.

Can we make this a sticky or perhaps put a few of these nice explanations where they can be seen at the top. I keep reading this trying to memorize it because it is so key to think of it like this (because this is what it REALLY is) while tuning.

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