suggested pressure
the "porter tips" for ext vaia
There are so many ways that you can adjust a multi-chambered air spring with independent volume adjustments as found in the EXT Vaia. Along with the Geometry adjustment options through fork height in the crowns and 44mm or 48mm offset adjustment in the crowns and multi adjust damper, the Vaia offers so many different ride possibilities!
The Vaia main chamber pressure allows the rider to set the support of fork for ride height
- The ++ chamber creates a ramp of support in the mid stroke because the main + chamber is a single, short, progressive air spring until the pressure matches that of the ++ chamber and adds its extra volume for more linearity.. This support ramp can be adjusted further into the travel with a greater pressure differential between + and ++ or can be earlier in the stroke with less pressure differential. A higher pressure in the ++ can solve a bottom out problem a lower pressure can create one.
- The shape of the second part of the air spring curve after the support ramp is dictated by the volume of the ++ chamber. You adjust the ramp up of the ++ chamber towards bottom out by reducing volume for more ramp and increasing volume for more travel usage.
- Allows the rider to play off trail against head angle independently. A slacker head angle can feel amazing at high speed (lots of trail) and more unstable at low speeds (lots of side to side flop). A shorter offset can bring that low speed stability back for more confident low speed handling. The higher offset can flatter a steeper head angle to make the handling faster for more aggressive riders.
- Of course the dual crown Vaia can also be raised or lowered on the fork legs (within limits!) to give an adjustment in head angle and front end height which coupled with under the stem spacers gives the rider independence in bar height adjust with different head angles and front end heights.
other suggestions
A dual air spring with a preloaded second chamber as in the Vaia’s + and ++ allows the rider to create a ’support ramp’ in the air spring. That’s because the + chamber is a single, short, more progressive air spring until the pressure increases to match the ++ chamber at which point it becomes a lengthening, dual air spring with more linearity… Because the feeling of ’support’ can come from quite shallow to quite deep in the travel there are a lot of overlapping adjustments that affect the ’support’ of a fork… reducing the negative volume in the Vaia can make the negative spring less influential into the + spring so you get a feeling of support earlier in the stroke. Changing the ++ pressure differential changes the amount of travel used before the ++ air chamber engages. The higher the pressure differential the deeper into the travel the support ramp lives and if the differential is lowered then the support tails away sooner. At the point where the ++ chamber comes into play, the rider can adjust the feeling of support from this point by adjusting the ++ volume. Adding volume spacers to reduce the volume makes the ++ chamber more progressive and creates more support in the second half of the air spring. Whereas increasing that volume can allow a less aggressive rider to use more travel, more comfortably in bigger terrain.
All of these adjustments help the Vaia rider to achieve a good feeling of balance with the rear suspension. This feeling of a bike ‘keeping its shape’ is something that can be the key to rider confidence. Keeping that bike shape and rider confidence at all speeds and in all terrain is where the geometry and rider shape adjustments on the Vaia can improve handling and confidence. The Vaia’s 44-48mm off set adjust allows the rider to play off trail (self centring stability) against head angle (steering) independently. A slacker head angle can feel amazing at high speed (lots of trail) and more unstable at low speeds (lots of side to side flop). A shorter offset can bring that low speed stability back for more confident low speed handling. The higher offset can flatter a steeper head angle to make the handling faster for more aggressive riders. Of course the dual crown Vaia can also be raised or lowered on the fork legs to give an adjustment in head angle and front end height which coupled with under the stem spacers gives the rider consistency in bar height with different head angles.