So I was thinking about the latest air shocks for the DH crowd, and the trade off that we often have to make between a lively, poppy bike and a ground hugging, stable race machine.
I had an idea that might make it possible to achieve a lively and uber-sensitive, high traction suspension setup and bridge the gap between progressive and linear suspension.
Could you make an air shock with a shaft-speed sensitive spring rate? In other words, a shock that had a given spring rate for low to medium shaft speeds (for pedalling and popping) and then opened up to a softer spring rate at high shaft speeds (high speed rough terrain and chatter). This has never been possible with a coil spring, but seems doable with air.
I realize that we have damping that does this. The problem with using damping to resist motion at low shaft speeds is that it dissipates energy - our energy - making the bike feel dead. But achieving this through a variable spring rate would not dissipate energy. The suspension would remain lively and poppy.
So I guess you'd use some kind of inertial valve that increases the air can volume instantaneously with high shaft speeds.
I don't know, maybe this has already been done in air forks? I can't believe that someone else hasn't thought of it. We do have low-speed blow off valves, etc. I haven't studied how they work, but I'm guessing it's tied into the damping, not the air spring. I figure some of you suspension gurus will know more than I do...
PS - Someone under 18 ought to submit this to that Pinkbike contest and get Cane Creek / Ohlins working on it.
I had an idea that might make it possible to achieve a lively and uber-sensitive, high traction suspension setup and bridge the gap between progressive and linear suspension.
Could you make an air shock with a shaft-speed sensitive spring rate? In other words, a shock that had a given spring rate for low to medium shaft speeds (for pedalling and popping) and then opened up to a softer spring rate at high shaft speeds (high speed rough terrain and chatter). This has never been possible with a coil spring, but seems doable with air.
I realize that we have damping that does this. The problem with using damping to resist motion at low shaft speeds is that it dissipates energy - our energy - making the bike feel dead. But achieving this through a variable spring rate would not dissipate energy. The suspension would remain lively and poppy.
So I guess you'd use some kind of inertial valve that increases the air can volume instantaneously with high shaft speeds.
I don't know, maybe this has already been done in air forks? I can't believe that someone else hasn't thought of it. We do have low-speed blow off valves, etc. I haven't studied how they work, but I'm guessing it's tied into the damping, not the air spring. I figure some of you suspension gurus will know more than I do...
PS - Someone under 18 ought to submit this to that Pinkbike contest and get Cane Creek / Ohlins working on it.