Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Jester]

Was discussing this with a mate (at the pub, as you do), about whether having different fork damping settings on each fork leg is inherently dangerous or not; he says it is, I say it isn't.
Now I would never set my own settings to be different and I wouldn't suggest anyone else goes againt manufacturer specs either, though I reckon it isn't the disaster matey reckons it is. Surely as the forks are effectively clamped together at the bottom by the wheel spindle, even if they want to move at different speeds (which of course they will want to with differing damping rates), they can't due to the spindle. They MUST and DO move together as one effective suspension unit and you get a combined damping rate.

Consider this extreme example - set both compression and rebound rates to max in one leg and min in the other, you effectively get 50% overall. The forks will still move together and the stability of the bike isn't compromised.

Some new bikes actually have rebound controlled by one leg and compression by the other, therefore each leg must have zero compression and zero rebound damping respectively.

Obviously it's best to have the forks set to the same so you actually know the exact settings. I reckon matey has a point if the vehicle has 4 wheels that can move independantly and different damping on each corner could unsettle the vehicle, but on 2 wheels I say not, possibly in the past with thin forks and weak yokes\frame with lots of flex, perhaps, but not now given the rigidity of components nowadays.

Any opinions?

[Jak]

I know you can fit different rate springs in each fork leg to get an average rating and like you said, one leg can be set to control rebound and the other compression. I cant see that it would be dangerous at all and most riders would notice if the handling was off. 

[mc101]

They are clamped together extremely tightly and act as one mechanical unit so no it would hurt ...

[zx10r-Alan]

If there was zero deflection in the wheel, having different settings in each leg would be fine, however there is always some deflection as there are many sperate components which have tolerances in order that they can be assembled and disassembled with relative ease. These tolerances would allow the wheel to deflect slightly if the settings in each leg were different. But this happens anyway, as we're unable to accurately set each leg precisely without using sensitive measuring equipment.
Besides, would any of us notice the difference?

[HammyUK]

Ohlins actually state that you can offset rates to get an "average" setting in their manuals.

[zx10r-Alan]

There's lots of things you can do, but having one leg fighting against the other 'will' cause a degree of deflection in the wheel due to the small tolerances in the bearings, and the flex in the axle. It may or may not be detrimental, but it will happen.

[faulksie]

based on the fact that some bikes now have one fork leg for compression and one for rebound, then I'd say a difference between a click or two each side would not make a problem at all handling wise.

In fact if you think about, two legs doing compression or rebound, the combined force of both = total compression force, same as the one leg for each set up, and a fine adjustment could be made with the two legs system to better things. ie 10 clicks of each = 20 clicks overall, 9 clicks of each = 18 overall, 10 click of one and 9 of the other = 19 overall, which might be better than 18 or 20 overall. Not that I'd notice the difference, but someone like a MotoGp hero would.

Never considered this before, good topic Jester 

[Jester]

Cheers for the opinions, some good points there. The info on Ohlins from hammy is interesting, I guess this could tie in with the extra adjustment theoretically available as per faulksie's reply, though it could also at the very limit allow a racer to tune in a very slight preference in the bike to turn left or right depending on whether the forks are compressing or extending, and maybe for if a left or right hand circuit. The difference, if any, would be tiny given the minimal play or flex, though they do go for the last 0.0001% advantage so who knows what goes on here.

I guess the consensus is no harm to it at all, though pointless on the street with standard forks and non-god skillz

[HammyUK]

Ohlins non-road forks have been that way since before the FG270 pre-gas.
Right leg - rebound
Left leg - compression