A Heart of Metal chat with Rob Quirk, founder of Quirk Cycles.
Hi Rob, it’s great to have the chance to interview you, can you tell us about Quirk? When did you start frame building and what made you start?
Quirk Cycles was born back in 2015 out of obsession and frustration. My obsession with the bicycle was very deep – infatuated with its history, mechanics and engineering – the bicycle to me was this perfect fusion of artistry and function, and when coupled with the sheer exhilaration that comes from riding it, it is perhaps one of the greatest objects ever designed. Many people feel this, and back at the time when I started Quirk Cycles many people started to ask what is the perfect bike for me? Which sounds like an obvious question but at that time the industry was dominated with marketing road bikes built for the grand tours – like many others I did not fit this narrow category.
Many might remember that this is when the 25mm tyre was the next big thing (can you imagine 25mm was considered extreme and revolutionary). It was at this time that three grassroots scenes started to develop which really turned the cycling industry on its head – gravel riding, bikepacking and ultra-racing. There was this big push from the bottom up that demanded bikes could fit wider tyres, carry luggage, drop bars off-road, etc. The only thing big bike companies had that could come close to catering for these riders were CX bikes, but it wasn’t enough, and this is where Quirk Cycles comes in. Customers started turning to custom builders, and likewise custom frames started to lead the new developments in the industry. It was a period of great creativity and a lot of the new wave of frame builders came into existence at this point. It was exciting to see the industry lead by the grassroots for the first time since probably clunkers and the creation of mountain bike riding.
Although in the early days, Quirk Cycles was more concerned with the users end use, now there is a greater emphasis on the engineering and craftsmanship of the frames. A big part of this has been driven by the use of 3D printed titanium and stainless steel used in the development of proprietary parts such as dropouts and head tubes. My objective was to resolve various design challenges by utilising a 3D printed technology, focusing on factors such as reduced build time, better alignment, weight efficiency, and optimised stress distribution. Additionally, I sought to design a part that was not only visually appealing but also distinctive to the brand identity of Quirk Cycles.
When did you start using Columbus tubes? And why?
From day one Quirk Cycles has always used Columbus tubing as our tubing supplier. I was introduced to Columbus very early on and throughout the years have seen how Columbus has sat at the front of tube development, constantly researching and creating new metal alloys in the continuous search for improved mechanical characteristics and weldability. Over 100 years of experience in making tubes coupled with the clear superiority of their metallurgy knowledge means that I can be confident knowing the tubes will be up to task.
What are the most noticeable differences when working with the tubes? From a riding point of view are there any noticeable differences?
The biggest takeaway from using Columbus tubes is the quality of the base material. Welding is a joy with their consistency, cleanliness and perfect ductility. Columbus tubes have great malleability, even their stainless which as a material is notorious for being difficult to form and weld.
When it comes to ride characteristics of a frame this is always going to come from many factors more than just the tube selection, also the material, geometry, tube diameter, butting profile etc. It’s impossible to single out just one! This is why it’s important to choose an experienced builder such as myself as designing the best riding bike is a fine balance of all these qualities.
How would you define Columbus tubing in three words?
Progressive, Excellence, Dependable
Which frame would you like to share with us today? And which Columbus tubes have you used for this frame?
The frame I would like to share today is the latest Quirk Cycles evolution – which coincidentally is also Columbus’ newest development – the TITAN, a titanium road bike built using 3D printed titanium junctions, titanium fork and Columbus Hyperion tubing. Titanium was on my horizon for a long time but knowing that Columbus was re-releasing their titanium tube set I wanted to wait so that I could use the Hyperion tubes in order to work with a material that I could attest to its quality.
Many builders who build in titanium purchase stock in large lengths and cut to size. They will then butt (the process of thinning the wall in the centre of the tubes and leaving the ends thicker) the tubes in house, most likely using a lathe. Not only is this process lengthy and requires great skill, there is also a high risk of the butt being machined off-centre (removing more material on one side of the tube than the other). Instead I wanted to use a ready butted tube so that I could be confident of the high quality of the alloy. The result was the TITAN which I present to you here.
How does this frame compare to your normal production?
Apart from being the first titanium frame offered by Quirk Cycles, it is notable for also being the first to come with a titanium fork. The fork in this build is a prototype and consists of a 3D printed crown welded to fork blades, welded to CNC dropouts. The steerer is also titanium. Currently the fork is being developed to be completely 3D printed with a bonded carbon steerer. This is due to be released early next year and will be comparable in weight to a carbon fork but with the excellent ride quality offered from titanium.
The frame also features a 3D printed titanium head tube which brings cable integration to my frames in a way that doesn’t compromise on headset choice, as well as a 3D printed seat cluster that allows me to build using straight skinny stays for improved compliance and ride comfort, increased tyre clearance, and improved alignment. It also allowed me to integrate a seat clamp into my frames, removing my reliance on aftermarket parts.
Now my attention is turned to creating a constellation of printed parts to complement the builds so a Quirk bike goes beyond a frame. Already I have produced a titanium seat post as seen on this build, but on the horizon is a 3D printed titanium stem and bars.
Why did you choose these tubes, those diameters, reinforcements etc.?
My reasons for using Hyperion I’ve already mentioned but interestingly your question on tube diameters is one which I think brings up some interesting ideas. A general consensus for titanium tube size has often been based on an equivalence in steel. A titanium tube approximately has about 60-70% the stiffness of a steel tube in the same diameter, so going up in diameter is one way to replicate steel.
For a while now I have been wondering if steel frames are being built to be overly stiff? With the development of increasingly strong steel alloys, that can be drawn in super thin wall thickness, lightweight large diameter tubes can be made with little weight penalty.
These large diameter tubes also look reassuringly modern but what about the stiffness? Is the ride quality suffering? I think the question of stiffness is one of those topics that haunts the bicycle industry as stiffness has often been equated with efficiency but under testing isn’t necessarily the case.
So I spent time looking into tube diameters, deflection numbers, frame geometry and the effect on ride quality and decided with the TITAN to build with tubes that aren’t oversized to the same extent of some manufacturers. Initial tests have been promising with exceptional ride quality and with the improved stress distribution afforded by the 3D printed parts, an equally durable frame.
Is it the first time you have used this exact tube specifications?
It’s all new on this titanium build.
Could you explain the manufacturing process step by step?
Quirk Cycles has been entirely my endeavour and output for the past nine years and everything you observe has been crafted by my hands. I serve as the designer, manufacturer, consultant, and brand strategist.
Consequently, my workspace is optimised for efficiency with minimal tools. While many frame builders utilise extensive machinery such as mills and lathes, I have dedicated myself to creating a construction process that requires only a few key tools. This is made possible through additive manufacturing, which enables me to 3D print essential components of the frame using stainless steel or titanium, significantly enhancing the efficiency of the building process. As such construction is greatly sped up. All tube to 3D printed junctions consist of a 90° cut which can be executed by hand.
It is only the BB that tends to get the tubes mitred by machine, and for this I use an industrial belt sander which offers greater speed and accuracy of cut over a mill. The rest of the process is similar to how other builders would work, placing the tubes in the jig, tacking to hold in place, then welding and finishing. The greatest improvement to my process has come from the greater alignment accuracy offered by the 3D printed parts which has greatly sped up the work process.
After this the frame goes to finishing, which with steel will be paint, but in the case of titanium we can play with the inherent properties of the material and contrast surface finishes such as polished, brushed and blasted. Titanium also has the unique quality of when an electrical current is passed through it in a solution, it will form an oxide layer and the thickness of that layer will refract different colours of light back to the eye of the viewer.
On this frame you can see that the rear of the frame, and its logos have been brushed and anodised, then it has been bead blasted on the front for a durable raw finish achieving a mesmerising contrast between anodised lustre and raw titanium refinement.
Who are your customers, in general or specific? What are they looking for?
They are as varied as you can imagine ranging from bikepacking adventurers to discerning collectors of unique builds. It’s actually the best part of the job meeting people from all other the world and hearing their vision for their Quirk. It’s this meeting point where my ideas get tested, reinterpreted and reflected back at me and it’s this conjecture that pushes it all forward.
