Well this is exciting! Neko Mulally's Frameworks Racing is going to be testing and potentially racing a Reynolds 853 steel front triangle designed and developed here at Cotic. I have been working on this for a few months now, and it's great to finally be able to tell you about it.
Fort William
I first met Neko through our mutual friend Chris from Downtime Podcast. Neko is Chris' co-host on the excellent World Cup Post Race Shows, and we got introduced properly at Fort William World Cup. Neko came over to our stand and we had a good chat about frame design, details that matter. We was really open, and I am so impressed at how fast he has grasped the detail of suspension design. I gave him a bit of advice about trying to solve the fatigue cracking problems they were suffering from all last season on the aluminium frames. I am a just a big fan of World Cup DH racing, so we were all just super excited to have a bona fide World Cup racer chatting to us!
Worlds
When we got to Les Gets Worlds last year, we found that there were race teams pitting all over the place. Literally IN town; on driveways, in parking bays, on street corners, everywhere! I rolled down from our chalet to the other apartment we were renting at the bottom of the hill, and I noticed the Frameworks Racing pit just opposite. I was just about to head up to say hello, when Neko rolled out on his training bike, rode straight over, looked me straight in the eye and said "I've been looking for you. We need to talk steel frames!". He had to get going right then, but it still counts as one of the coolest things that happened that week!
Next day Neko and his mechanic Anxo come over to the Cotic stand and we had a loooooooooooooooooooong talk about race bike design, and using steel in particular. The plan was hatched that I would design a steel version of the front triangle they were racing - same geo, same pivots, just in steel.
At the time they were still fighting the cracking issues and I could tell Neko was frustrated. I cannot even begin to fathom the mental toughness he has to drop into race runs on frames with cracks in them! A different breed....
Frameworks x Cotic Collab
Although through extensive use of gussets they seem to have got on top of the durability issues on the aluminium frames, Neko was still keen to run steel and see if the ride feel or any other attributes would be an improvement for the race bikes.
On the long drive back from Les Gets, I asked Neko to send me the tube specs for the aluminium frame. I set about doing some stiffness and strength comparisons in my notebook using some simple beam theory equations, to get a feel for where we were. Stress = My/I for all you equation fans out there.
The really exciting thing from my point of view was that on that first look, our stock RocketMAX Gen4 down tube was a good deal stronger and stiffer than aluminium down tube on the first Frameworks frames. I started working through all the tubes on the frame and it became clear that we wouldn't need to do anything completely new or crazy thickness to get much improved global strength and stiffness out of the front end. Neko is also using a ZS56 standard head tube, but I already had that covered in my design toolbox. I used the same size for the RocketMAX Gen4 development so I could use reach adjust headsets.
As I got further into the design and engineering, Neko's good friend Dan - the Chief Designer and Engineer at RAAW bikes - got involved to design review my work. It was great to work with Dan, having only known him to say hello to at races before. It's fun to bounce ideas around, and having someone as diligent as him checking things is a really great part of the process. Dan's helped Neko out with the carbon design on the rear ends, so it was nice to be able to tie both ends of the frame together in this way.
Ultimately, the Frameworks x Cotic front end uses the exact same down tube as the RocketMAX Gen4, then the same size and spec tube for the seat tube. The top tube isn't Ovalform as it would be on a Cotic. We kept it round because I was a little concerned about dual crown fork stanchions hitting the thin edge of the ovalised tube. It's also two wall thicknesses up on the RocketMAX, because downhill.
After that, it was about getting into the details of the tube junctions and trying to reinforce the frame, whilst nicely managing the stiffness out of the reinforced areas. There's a lot of gussets!
Details
You can see the head tube and seat tube reinforcement. They're pretty obvious. The seat tube gusset design came from my experience with designing rocker link frames for our very first full suspension frame - the Hemlock - way back in 2006.
Neko wanted some adjustability in the frame for trying some different suspension rates, so the shock mount is a shuttle type design that can be flipped to move the shock pivot to reduce or increase the rising rate of the frame. There's also another shuttle for a third option. Lots of options!
Our friends at Five Land Bikes built the frames between runs of RocketMAX's, and we had it finished in Stormtrooper White by Cerakote Up North near Preston.
This is such an exciting project to be a part of, and I want to say a massive thank you to Neko and Anxo for putting their faith in me on this. It's been a privilege to get involved, but I'll admit to still being nervous. It's my first full blown DH bike, and although you can work the numbers and do the maths, it doesn't mean anything until the tyre hits the dirt.
With Neko's unfortunate hip injury, he'll be passing on testing to another rider, but we should hear all about it soon. I'll be on the Frameworks Racing episode where they go over it. There is still the possibility they will prefer the aluminium frame, but even if they do, I still got to design a World Cup DH bike, and that is so cool! Everything crossed it goes well!
Cheers,
Cy
Founder and Director
Cotic Bikes - A Truly Independent Bike Company Since 2003
www.cotic.co.uk
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