Rebound damping - what\'s it do?
 

OK I understand what rebound damping does, it slows the speed that the spring returns from a compressed position - that's the theory.

But what does it do? what difference does it make?

Riding a local bumpy piece of road I played with the compression damping, up/down 4 clicks - very noticable difference, I now have a wet riding setting.

I did the same with the rebound damping, to be honest I didn't really notice anything?

Can someone "enlighten" me as to what I should be feeling? Maybe the roads in Switzerland are too smooth.

You've just put me to shame, as I can't be arsed tp play with the suspension ..... but maybe that's because in and around Zurich you can never get up to more than 60 KPH before hit a traffic light or a pedestrian crossing.......

It's down to when the weight of the bike shifts between the front and the rear, usually in corners when you come off the brakes and onto the throttle.

If there is no rebound damping, the bike will "pogo", shifting the weight between front and rear in the corner.

Obviously this is an extreme case, but not enough rebound means the weight shift from front (on the brakes) to rear (on the gas) as you come out of the corner happens too quickly and varies the front grip too much so you may lose the front.

Other effects are that it may just unsettle the bike or not feel safe on mid corner or during brake/throttle transition.

Have a look here for more tips:
http://www.v-twins.cc/info/AdjSusp.htm

The other effect of too little rebound damping is the bike will 'wallow' on the gas coming out of a corner-it's the weight transfer thing again. Too much rebound damping will cause the suspension to 'pack down' on a bumpy road. Basically the damping will reduce the amount of travel until you have none left-not a good idea.

John

So unless I feel wallowing in a turn I should leave it alone.

I guess I was expecting a smoother ride, i had read that one of the reasons for being thrown out of the seat was the spring returning too quickly after being compressed by a bump.

Wasn't there a recommendation to increase the rebound after increasing pre load? To set my static sag I increased my pre load as I weigh in at 85kg?

swiss 998,

try to imagine what the suspension would do with no fluid in the forks / shock, just springs. The bike would 'bounce' up and down on the springs - like your misses on a mattress.

The purpose of the fluid in the suspension units is to 'dampen' this bouncing, so that it is much smoother, and hence make the bouncing motion less pronounced.

In addition, as the suspension moves it forces fluid through a small aperture, the size of which is adjusted by the screws that adjust rebound and compression damping. The greater the aperture, the more readily the fluid flows and hence the less the 'damping'.

Slight adjustments in either compression or rebound will only really be noticed under extreme riding - e.g. hard braking, or accelerating hard out of a corner etc.....

Bottoming the forks out
 

Also remember in an extreme case if you set the rebound so the forks cant recover from compression before they compress again the forks will end up bottoming out. The rebound impacts the speed of return after compression, not enough means the forks will bottom out and too much will be like riding a pogo stick.