Hows Rebound Work?

Compression: takes/deals w/ the initial hit. In a perfect world, you want enough play (aka action on the compression stroke) to bottom once in the most extreme case per lap/outing. Bottoming consistently says somethings not set up right - period. Better yet, you don't want to bottom... you want to use all the travel except .5mm over the biggest hit. Like I said, perfect world and completely impossible to prep for.

Rebound: simply modulates the air/oil flow as the spring returns to its unloaded state. Say you're on a dead-flat 100M surface riding @ 30kMh. The one and only depression on that stretch is straight ahead. Your bike hits it and the fork goes into compression. Once you begin to unload, the rebound valve "clicker" (damper setting) will tell the air/oil how quickly to pass thru the valve. It may happen slowly or quickly depending on what you've done. Why does that matter? In theory, you want to be set up the same for the next bump as you were for the first. You want all of your compression stroke to deal with the following like-sized bump. If that bump is very close, you want very quick rebound. You don't want 100% of your compression stroke for the first hit then only say 40% of the compression stroke for the next hit of the same size. That's called packing and it diminishes control. When you loose control, it's over.

A spring is a spring; a stupid piece of engineered metal, and it does nothing more suspend a given rider's weight relative to their ability/skill. It's the air/oil on the compression and rebound strokes, and the movement thereof, that really mean something.

Air/oil is used top and bottom (compression/rebound valving) to modulate fork/shock action. The principle is the same front & rear (fork & shock), only the results differ and their subsequent impact on control.

The ONLY WAY to truly understand it is to go out and run to the extremes of all your settings over the same piece of terrain and note the differences. You can read about it all day long and everyone and their cousin has their take, but until you know what the extremes feel like, you won't know much. It's very easy to do and I'd suggest going to the extremes first off rather than stepping thru progressively softer/harder settings. That's fine for later on, but initially, run the extremes over the EXACT same piece of terrain @ the exact same speed, etc. and the difference will be as clear as day.

I need to add that not everything that you (a rider in general) might think is a suspension problem is. Rider position plays an equally important role too.

Ok.. some basic suspension stuff.

Springs in the form of gas or metal coils hold the bike up. The shock body contains fluid based dampers to control how fast the springs work in each direction. When compressing the spring the compression damping offers this control. When rebounding from being compressed the......yep, you guessed it.. the rebound damping controls this action.

Some shocks and forks have multiple damping circuits which are high and low speed. Low is for stutter bumps and the initial portion of the stroke and high is for bigger hits.

Sag sets the static position of the spring. This is your load with gear on, on a stationary bike. Rule of thumb seems to be 20 to 30 percent of available travel in the rear and 15% to 20% in the front.

When trying to figure out what does what with damping settings remember this simple rule: Compression is for comfort… Rebound is for control. Example… you're hauling a$$ down the trail and you hit a square edged bump and BAM!! Your seat smacks you in the butt and your wrists get jarred. That is uncomfortable and is controlled with compression damping. Less compression allows the spring to compress quicker…more slows it down a bit. Next.. you hit a g-out or a drop and the fork and shock compress almost 100% and then bounce back like a pogo stick causing you to not be able to hold a line or even crash.. (not enough rebound damping) or you hit consecutive smaller trail bumps and the suspension packs down and does not return to full or near to full-travel, eventually leaving you no available travel (too much rebound damping). These are control issues and rebound damping offers the solution.

Lastly, when you make adjustments WRITE THEM DOWN!! Also don't just start spinning dials, twist everything full clockwise and then back it out 50%.. Start from there. Righty tighty, lefty loosey. Tightening the dial adds more damping effect, loosening it lesions it. Lastly, asking someone what they use for settings is tempting but what I like in a bike and what suits my skill level may be unridable and even downright frightening for you.

Reminder... work on your settings after riding the bike agressively for a bit to warm up the oil in the shock and fork.

bad mechanic said:

No, compression for control and...rebound for control. It's all about keeping the fork taught and under control, providing the most traction all the time.

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This is a beginners forum,right? Hell most of these folks still think it is dampening... you know like babies dampen diapers, and that's ok we ll start somewhere... So let's make it easy to understand. I challenge you to find an easier way to explain which damping circuit invloves what than the "Compression for comfort, Rebound for control" bit. Many manufacturers make dampers that have factory pre-set compression and are only rebound adjustable.

Sure you can get all complex...as I can too, with mumbo-jumbo about shim stacks, progessive or straight wound springs, multi-speed damping circuts, the effect of linkage ratios on suspension action, etc.., etc...etc... But in reality all Joe Novice, hell or Joe Intermediate needs and more than often wants to know is "I hit X and my bike does XX, what can I do to make this better".

1) What is your tire pressure, 2) Have you set your sag.. and if these are in the ball park we work on rebound and/or compression settings as appropriate and where available. some suespension

The KISS principle is very effective when it comes to suspension

STT GUY said:

I challenge you to find an easier way to explain which damping circuit invloves what than the "Compression for comfort, Rebound for control" bit.

The KISS principle is very effective when it comes to suspension

Click to expand...

Spring rate or air pressure-supports your weight-should be set first, 25% sag (or manufacturer rec.) is usually a safe place to start

Compression-keeps the fork from compressing uncontrollably (brake dive and landing from drops are good examples of what compression can control)

Rebound-keeps the fork from rebounding uncontrollably-keeps the susp from "pogo-ing"

Once spring rate is set, start with comp and reb nearly full-fast. Add more damping (slow it down) to either setting as the need arises.... spring rate can also be adjusted, but within reason... don't try to run too little spring rate and compensate with too much compression damping and vice versa...

Pedalling platforms, lockouts, and such will all have an impact on the ride as well, but start with them wide-open... then start using them on smooth climbs to see if you feel an advantage-different suspension designs and riding styles will have different needs for these settings

Can't really get any more simple than that. Just because the guy may be a beginner is no reason to intentionally leave out basic info.