Rob’s prototype gravel bike
After working with Craig Edwards and Cane Creek on a prototype high-volume-tire EE rim brake, I was asked to build a show bike for Sea Otter to show off the brakes and other Cane Creek products. This gave me a chance to try out some construction concepts I had been working on. The first is the lightweight truss fork. I previously built a truss fork for my mountain bike, which performed really well. I thought I could create a similar fork that would be lighter than a conventional fork, through using the strength of triangulation, and that would also distribute forces better across the headset and frame.
The brakes will comfortably clear a 44mm tire – I wanted the frame to do the same, but also wanted to keep the chainstays very short, and fit a double crank. The pinch point comes at the chainstays to fit the stay between the tire and the chainrings. On the mountain bike I elevated the chainstays to remove this constraint. On this build, I experimented with using double tubes of a small diameter to minimise the width but retain the strength of a regular chainstay.
The build is completed with Shimano Di2 and an Ogle Components derailleur cage, with Hed rims laced with Berd composite spokes. Custom Powderworks added the beautiful chameleon paint, and the final weight is 16.9lbs.
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English Cycles is Rob English, 
winner of Best in Show at the 2013 North American Handmade Bike Show. Custom bicycles built in Eugene, Oregon, USA since 2009.
Cool! Nice to see a gravel bike with rim brakes. I hope Cane Creek will sell these brakes as a regular product. What’s the weight of the truss fork?
The fork on this one weighs 592g. Hoping Cane Creek will make more of these brakes, definitely a fair amount of interest.
I would definitely buy a pair of these brakes! Just curious, what do you think the max tire w/fenders would be for this brake? I’m hoping they might clear 42s with fenders… but probably a tall order. Also, do you know who I should bother at a Cane Creek to get them to manufacture these brakes? 😀
Hi Hans,
In talks with Cane Creek; hoping a production version will happen! Please bear in mind that they do need a custom frame and fork to fit to owing to the spacing of the direct mount bosses. 42 plus fenders might work, depending on the rim, tire and fender combination….. loads of room for 38s and fenders.
thanks,
Rob.
I like the special details – especially the chainstays! Do you think, the stiffness ist sufficient even when riding with bags? And ofcourse – the fork is very special. I’m curious how it performs.
Would the truss fork tubing on this bike be a little beefier than the disc gravel bike’s one?
No, pretty similar tubing specs. The disc brake puts more loading on the lower section of the fork than the rim brake.
What bar tape is this? Really cool frame by the way.
Mark
Bar tape is from Silca.
Very unique/clever/lightweight design no doubt about it but I see two possible problems – that “thinned out” rear triangle I suppose it works like a suspension calming down the vibrations and impacts – if it allows vertical travel – but does it still perform in a “snappy modern bike” way? The other problem is that the seat stay (above the rear brake) looks like a needle trying to enter the seat tube, smells like inviting an early fatigue cracking to me…
Hi Arthur – thanks for taking the time to comment. The rear triangle does not allow any vertical travel, this has been tested in a static loading and compared to a more conventional arrangement. That same testing revealed that the lateral stiffness is less; through riding I am seeing if I can feel this difference. To get a better sense I really need to install control tires/wheels for a straight frame comparison. Just riding it I can so far say that it rides nicely, doesn’t seem to be missing any ‘snap’.
The wishbone seatstay arrangement is a design I have been building with for 14 years and hundreds of bikes. The loading here is actually quite small, and the real world experience shows that there is no tendency for any fatigue failure in this area.
thanks, Rob.