Rebound is doing the opposite of what you want the oil in the shock to do. With 0% rebound, the spring is ALL of the force pushing the shock shaft out of the body after compression. With xx% rebound, the pressure in the shock is pushing the shaft out, along with the spring.

So, 0% rebound seems to be the lesser of two evils. If you run too much rebound, you may have an odd handling car with roll characteristics that depend a lot on how you take the corner. If you run 0%, all of the compression and decompression resistance is maintained consistently by the spring.

A little rebound is helpful on a low grip surface but it really isn't needed on high grip surfaces such as carpet. Just my 2 cents.

I have done my shocks many times and bled them correctly by the XRAY instructions, but it states in the setup sheet not to use the shock shaft oring (970050) and I am trying to find out where it is. I know there is one in the bottom cap but I think if I don't use it the oil will leak out. I tried to get 25% rebound with the shocks assembled per the instructions and it seems impossible.

Then you aren't doing something right. I can assemble my 09 shocks right out of the book, quick and dirty, and get 100% rebound without doing anything special at all. I then have to bleed my shocks with the lower cap to get the amount of rebound I want.

The shock shaft o-ring is when you put an o-ring on the shaft after it is in the shock body, so that it limits the up-travel of the shock. It is usually just to stop traction rolling, and give the chassis less roll.

With bleeding shocks; i run no rebound in my Xray Alloy Shocks. It is achieved by a 1mm hole as people have mentioned. So before i put the shock bladder in, i will push the shaft up about 3/4, i will slide the bladder in so it can get out all the excess oil, then i screw the cap on about 1 turn. After that i push the shock shaft all the way up and hold it there, whilst tightening the cap.

That should give you a Zero-25% rebound, perfect shock.

Hope this helps,
Ryan.

Not exactly. Rebound (or lack thereof) is given by the volume of oil displaced by the shock shaft, volume which is small but not zero. Bleeding the shock with the piston all the way up ensures that the shock shaft volume is accomodated in the shock when the piston goes all the way up. The shock will then tend to return to this state all the time because when the piston goes all the way out, there is a pressure differential in the oil which sucks the bladder down a teeny weeny bit. If the space above the bladder is vented to the atmosphere, bladder deflection is compensated for and the shock will tend to return to its rest position under bladder elastic force alone. If the space above the bladder is not vented then the pressure inside this space drops, so the air inside will contribute to sucking the piston up again, alongside the bladder elastic force. This means the shock shaft return is quicker as the force pulling it back is greater. Drilling the shock caps slows down the reaction of the shock. The effect is felt on both up and down travel of the shock but it does not affect how far the shock will rebound. This is only affected by the oil volume inside, so you need to bleed the oil as per instruction manual keeping the shock shaft extended to the desired position. This will ensure the volume of oil in the shock is adjusted to the desired rest position of the piston/shaft.

Really? My can dance too.:lol:

Get over the use of "art", it's a common expression, in this instance it was being used to describe the arrangement of liquid and solid geometric forms along with tension, to appeal to our senses and emotion.

Granted, it takes specific knowledge and skill to be effective on our cars but, it is still done with passion, imagination, and intention. No voodoo or obfuscation necessary.

I agree, but most people understand that there is some sort of secret only the initiated have access to when expressions such as this are used. Specific knowledge is easily accessed these days.