When I make a batch of bikes, some parts of it I know exactly what I want to do, totally committed. Then other parts take a while. While the basic structure has been worked out some time ago, some assemblies I am seeing for the first time. I wanted to align the forces more directly on the rear shock mounts and improve the clearence for turning the adjusters. I had an idea that I wanted to try that would not only increase the strength but also achieve the goals mentioned above.
From purely a engineering perspective this machine is really unusual.
Not that it should be. It's just surprising that no one has
"discovered" it as the new best thing. The shorter swingarm helps rigidity and because the chainstays do not have to "squeezed" so
narrow they are still tube and stiffer than a narrower solid section.
The whole rear of the frame weighs less than just the R9 swingarm. I am
pretty sure it is at least 2 or 2 times the stiffness. I was able to
move the bearings outboard quite a bit. I used to feel that narrower
Q-factor was much better for making power. I still feel that way but
the wider 83mm BB shells and Q factors make some good things happen. I
am using these huge 30mm double-row bearings that are spaced a full
50mm apart with a 17mm axle. The drops are 150mm apart are MAXLE ready
and are light and solid burl. Pinch bolts are NOT required on fully
triangulated swingarms.
I slightly under-drove the shock to take better advantage of what new
dampers have to offer. You can set this bike up tight at the ends of
the stroke and it will sprint like a hardtail and take hits with grace
and control. The low frame weight is a result of a drastic reduction of
machined parts and hardware. The gussets have actually increased in
thickness by 15%. The frame weight of these machines will allow a
drastic reduction in the amount of work required to bring the bicycle
up to speed. In addition, it's reduced initial leverage allows easier
"lifting" to backside objects so much so that you can "pop" and fly
over stuff with amazing ease. The chainstays aren't short with a tape
measure but riding the bike, again because of the rearward pivot it
feels short and very snappy.
Needless to say I am beyond excited to ride my F-bomb. I have all new parts on the way for my own bike and I will be attending races and tuning sessions so we can get dialed early.
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