Compression vs rebound speed

How does compression and rebound dampening force "typicality" compare to one another? In other words if they were 50/50, the shock would have an equal amount of absorption in both directions..

How does this ratio change between road racing, off-road racing, regular street vehicle?

 

There is a whole science behind it. There are numerous factors that go into settings for a specific application. There are two types of compression. High speed and low speed which refers to "shaft speed" not vehicle speed. High speed compression is basically stutter type stuff and quick fast jarring hits (potholes, speedbumps etc) and slow speed is more like cornering, accelerating, stopping and smooth (if you will) jumps if that makes sense. Rebound is basically controlling the rate at which the spring returns the shock to its at rest position. The spring rate/preload also affects the ride height. Suspensions should be set up with a certain amount of sag as well. You don't want the vehicle sitting at the top of it's shock travel in a static state. Ultimately you want the suspension to react to input and return as quickly and smoothly as possible in order to absorb the next obstacle. If the rebound is too slow, the suspension will 'pack" meaning it will stay compressed from one obstacle to another hindering it's effectiveness. If its too quick the ride quality suffers, the suspension can top out and the vehicle can be unpredictable. If the compression is too soft, the vehicle can feel unresponsive and will bottom easily. If it's too stiff, it will not absorb impacts effeciently and the vehicle may deflect over bumps instead of absorbing them. Off road vehicles are typically set up to be more compliant over longer periods of travel as the obstacles are usually bigger. Road race vehicles are typically much stiffer and have way less travel. This also allows a lower center of gravity and allows the vehicle to be more stable at speeds in corners. Traction on a road course is just as much about proper suspension loads as it is tires. Daily drivers are always a compromise for obvious reasons.

So there is no real "carved in stone answer". The rate of compression vs rebound is going to be effected by vehicle weight, terrain, driving style, personal preference, how well the vehicle suspension is balanced, available travel and a myriad of other things.

I'm no suspension expert most of my experience is with off road motorcycles, snowmobiles. Maybe someone from one of the shock places on here can chime in and add some professional insight. I'm probably only half right lol

 

Thanks for the in depth response but this doesn't address my question. I know what each of them are as well as tuning with high and low speed. What I'm looking for is the RATIO of force absorbed between them.

 

My bad I misunderstood what you were asking. I believe the general consensus is 2:1 rebound dampening vs compression, due to sprung vs unsprung mass. But that's probably still not what you're looking for. Maybe I'll just mind my own business lol.

 

Do you remember where you saw/read 2:1?

 

What do you mean by "force absorbed" in connection to rebound? Rebound controls the RELEASE of energy stored in your vehicles springs once compressed.

 

Honestly, I don't. I've visited several sites and read many articles on the web about shim stack valving and suspension set up for snowmobiles. I remembered seeing some truck info on Bilsteins site so I just jumped on that and there's a knowledge section that explains basic suspension dynamics without much science if you want to check it out. That particular info said compression is about 25% of the dampening force and rebound is roughly 75. Most of my stuff is bike/sled related so there may be some variance there as well.

ETA: Found it. Site is called shimrestacker.com

https://www.shimrestackor.com/