The WhiteCrow Hub is fully mechanical and based on completely new air-closed concept.
Obviously there’s an air pump within the hub. However, we have introduced a mind-blowing game changer: The Air Pump is used to deflate the tire!
Because the WhiteCrow Hub is completely air-closed, external air is never sucked in from a potentially very dirty environment. Instead, when deflating the tire we store the air in a “reservoir”, which is always at a pressure higher than the tire. This way, inflating the tire is effortless and, obviously, clean. And this displacement of air between tire and reservoir can be activated as many times as you like.
Tire Deflation
Tire deflation is achieved by compressing air from the tire into the reservoir. Inside the WhiteCrow Hub there’s a relatively large air compressor driven by the wheel rotation itself (the Air Pump).
Tire Inflation
Tire inflation is very simply achieved by releasing air from the high-pressure air reservoir into the tire. The WhiteCrow Hub has a simple bypass valve enabling this. This process is totally effortless and quick.
The best Air Reservoir possible
For mechanical efficiency the actual volume of the air reservoir should be as large as possible. (Some high school fundamental gas physics will help you with this). To optimize this, we have decided to put the reservoir where there is more space and where it can help us the most: inside the tire itself. We leveraged this design from quite an old idea coming from Motocross (and recently commercialized for mountain biking by Schwalbe as ProCore.)
Air Reservoir Advantages
- It prevents tubeless-ready burping.
- It protects the rim from nasty knocks when the tire pressure is very low.
- It facilitates mounting tubeless -ready even in non tubeless-ready tires & rims.
- It allows for efficient rolling as there is no contact between the inner surface of the tire and the reservoir (except when you hit something hard, see above point).
- Finally, weight is saved by allowing for the use of ultra-thin rims when this would normally be too risky.
Energy Efficiency
At WhiteCrow Tech we have taken great pains to achieve a fully mechanical design. This means it’s the rider who has to exert energy at some point or other (Sorry guys, no doping here!!!). That said, for starters it’s way easier to drive an Air Pump with your legs and exploit the stored energy in the forward motion of the bike than use your arms normally would!
We’ve also understood how it’s usually easier during most rides to provide effort to run the Air Pump when deflating the tire. For example, we normally like to climb up a smooth section at medium-to-high pressure, then drop into low pressure to ride down a technical single track. So you can always inflate your tires for free and also deflate them for free, whether you’re on a typical technical single track or simply downhilling. And if you find yourself with no option but the need to drop pressure to uphill, your own bike gearing will also help. Our upcoming performance analysis page will further clarify this.
Finally, there’s a safety advantage: in case of emergency it’s always easy & quick to inflate the tire to improve the handling of the bike when accelerating to very high speeds.
INSIDE THE WHITECROW HUB
Our hub is a bit of an engineering marvel, and probably the most audacious piece of technology introduced into mountain biking since the times of the first oleo-pneumatic forks. Moreover, while the first suspensions and disc brakes were “ports” of technologies initially developed for motorcycling, our hub is a genuinely brand new kit.
The Air Pump
Certainly the greatest engineering challenge, our Air Pump has no pistons and only two mechanically-actuated parts (with a core eccentric that translates rather than just rotates). This allows us to achieve an all-temperature range as well as an ultra-light all-polymer design. Moreover, when the pump’s not in use it doesn’t generate any parasitic drag. We’ll show you a more detailed “insider view” of our exclusive Air Pump design in upcoming updates to this page.
The Command Clutch
The clutch is commanded from the handlebar via a shifter cable routed along the bike’s frame and through the center axle of the wheel. It has three positions:
1. Inflation: Air Inflation through air release valve (Tire Inflation Valve).
2. Rest: Nothing happens here, move on people!
3. Deflation: Torque-modulated air-inflation through Air Pump actuation.
The Hub Body
The lightweight oversized design with large flanges allows for spoking ultra-strong wheels. The body is also designed to provide for maximum all-weather-proofness (we live in Belgium and we’re experts at knowing what extensive mud damage looks like!).
The Freewheel
To be released in both Shimano and SRam 11x versions, it provides over 130 engagement points… Nice, isn’t it?!
The Rest
Obviously, we’ve designed our hub for easy maintenance. We’ve also included safety features to easily overcome most potential problems during your ride. We will be releasing more information about mounting the hub on your bike and the rest of the hub internals in the upcoming weeks.
Join us and we will welcome you into the adventure of re-inventing the mountain bike wheel!
