Fraser Britton interviewed Fox Racing Shox's suspension gurus Justin Frey and Mark Fitzsimmons about the new 40 RAD fork, which has been absolutely dominating the World Cup DH series since its World Cup debut at Val Di Sole.
How long as the 40 RAD been in development?
Justin Frey with the prototype Fox 40 RAD fork. Frey has been there for every step of its development process.
|The prototype FOX 40 RAD that our top athletes have been testing and racing since Val Di Sole has been a two-year development project in the making. RAD stands for "Racing Applications Development." The past couple of years we have been testing various chassis designs with our top athletes in an effort to fully understand each design's positive and negative characteristics. We have taken that testing data and designed the new chassis that is being raced on now. As for the damper and spring system; we started testing and racing that towards the end of last season in our current 40 chassis. We had our first official World Cup test session on the new chassis in Leogang, Austria where the World Championships will be this year the week prior to Val Di Sole. Due to travel logistics, we held a test in parallel with Aaron Gwin at the US Pro GRT race in Plattekill, which Aaron won the race on the new fork. Going into the Val Di Sole World Cup, we were happy with the test results and it showed as we swept the men's podium for the first time in the 40's history. |Fox 40 RAD Features
The original Fox 40 is nearly a pound heavier than the RAD prototype on the right - and yet Fox says that the new chassis is at least as rigid.
• Overall fork weight is reduced by almost a pound while keeping its stiffness.
• New spring system that adds more adjustability
• Retuned RC2 FIT damper developed to work with the new spring system.
• redesigned axle clamps
• Pressure release valves
• Updated lower friction seals
What are the major differences designed into the new 40?
|The goal of the project was to give the riders a lighter fork with similar stiffness characteristics while reducing chassis feedback into the hands and arms. Which in the end reduces rider fatigue. The fork has a new spring system that offers more adjustability than the old one, it is lighter and changes where the weight is located in the fork. This helps with making quicker left-to-right transitions of the bike. The damper was retuned to match the new spring system.|
Fox 40 RAD Prototype - post-mount caliper bosses.
Is the 40 RAD still in the R&D stages, or is it dialed in enough to be ready for production?
Air-bleed valves on each side of the lowers.
|We continue to learn and make small changes to the fork based on rider, mechanic and field testing data. We will release more details later in the year as to the specifications of the production version. The plan is for it to be a 2014 model.| How much influence have Fox-sponsored athletes had in the development of the 40 RAD?
The new dropout system is much more compact.
|There is no better place to develop high-end product than with the best athletes in the world. They are always looking for that extra edge of performance and their feedback is as honest as it gets. It they feel they are at a disadvantage, they let you know it. They also push the product to its limits and if it lasts a season to their abuse, the paying consumer reaps the benefits.|foxracingshox.com
Each racer gets a custom name plate on the crown.