Bike Check: Liam Stanley's 24" Titanium Darwin Designs Dirt Jumper

Unequivocally, the Darwin Designs 24" Ti DJ is the Stanley's pride and joy. I chatted more to Liam about his riding ambitions and learned about Patrick's education, frame-building history, and appetite to progress his brand.

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Liam Stanley

How did you get into riding bikes?

When I lived in Australia there was a skatepark on our block. My brother and I would ride our strider bikes on the halfpipe. My family spends a lot of our holiday time and weekends on biking trips, and I’ve been able to ride a lot around BC for the last few years, so that has helped.

What is your favorite part of your custom bike?

I really like the 3D printed chainstay yoke and the custom wheelset. Also, it’s easy to get tailwhips around. I was worried I might struggle going up to a bigger bike from my 20” but that’s definitely not the case.

What is your preferred style of riding?

I’m stoked on steeps, loam, and brown pow lately. Techy DH in general is my favorite if I had to pick one but I still love trails and DJ.

What is your favorite place to ride?

Kamloops because they have the Bike Ranch and an awesome trail scene. There are a bunch of awesome people to ride with in Kamloops.

Who is your favorite rider?

Can I have a top three? Erik Fedko, Liam Baylis, and Jesse Munden.

Who do you look up to outside of the biking world?

My physio, Jeff, because I want to be a physical therapist when I’m older. Studying physio will help with bike training and injuries, and I can help athletes like me.

Do you have any goals, ambitions, or tricks you'd like to accomplish?

By the end of the season, I want to learn to flat-spins and improve my sui-bars (suicide no-handers to bar spin combo).

What events will you be participating in this year?

I'll be heading to the Big White Bronze Slopestyle Events as well as the Fernie and Silver Star BC Cups to race downhill.

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Patrick Stanley - Darwin Designs

Who or what is Darwin Designs?

Darwin Designs is an engineering and design company that started as a passion project to make one bike. It evolved into an opportunity for my kids to learn design and fabrication trades, and more recently I’ve partnered with friends who are engineers, designers and athletes to continue pushing our capabilities. I grew up in a family business, I suppose Darwin is my take on (modern) family business. We’re stoked about testing new technology, building bikes, and supporting athletes who live to ride.

Where is the company based?

Our shop is in the West Virginia suburbs of DC, but being forced into remote work over the last few years has opened the opportunity to travel and collaborate more readily with engineers in Europe, Asia, and Canada. Fortunately, the design side of cycling can be done from anywhere with a connection to our software cloud. I’ve designed frames from the beach in Hawaii and a campground by Whistler (insert idyllic Instagram post of a guy with a laptop in a hammock by a glacial lake) … lately we've been exploring the scene in western Canada. It’s tempting to move to BC full-time!

How did you arrive at building frames?

I grew up turning wrenches in our family auto garage and trained as a mechanical engineer at Drexel University where I spent evenings in the machine shop. After university, I worked in a refinery and was taken on as an understudy to a metallurgist and a welding foreman. Over the years I pieced together the skills for design and fabrication.

A good friend of mine (WilcoCycleworks.com) started building fillet-brazed frames and he pushed me to explore building my own. Then in 2016, my custom stainless steel hardtail mountain bike was stolen, and I was determined to reproduce that one-of-a-kind bike. I built serial number 000 with hand files and a torch. It was rewarding (and accessible) to start with the most basic process - building this way, by hand, helped me to discover which aspects of the process I was drawn to, where I found value and where I didn’t.

You can build a damn good bicycle frame this way with practice; it’s an art. Freehand building quickly evolved into more machine-focused processes with custom fixtures and jigs. We built up a professional level set of custom tooling, each with a dedicated purpose to produce parts of the bicycle frame. The engineer in me can’t resist continuous improvement, so I’ve been exploring ways to simplify these complex production methods through additive manufacturing and cloud-based collaborative design software.

What is special about Liam's DJ bike?

It's designed to complement his riding style and his physique. Liam has an innate sense for bike feel, and he's built like a gymnast – he can connect the dots between frame geometry and setup, to his bike’s response when he is dialling in tricks. So Liam tested a bunch of different bikes and took notes on how they felt different. Based on his notes we adjusted the geometry and the build to suit. What else is special? He led the design and ran the mill, saw, and tube bender to produce the frame while I did the welding.

Can you run us through the construction methods, materials, and why you chose them?

We start with titanium tubing sourced from North America – the good stuff comes at a cost, but I’d rather spend a bit more knowing the provenance of the material versus cheap stuff of unverified quality. The tube set is oversized at 35mm and 42mm diameter top and down tube respectively to make a relatively stiff chassis. For this frame, we used an integrated headset head tube and sliding dropouts with tensioners from Paragon Machine in CA. Mark and the team produce top-quality parts. Their integrated head tube fits a standard BMX gyro perfectly, and the dropouts have slick integrated caliper mount and tensioners, so it was an easy choice.

As I mentioned, our current frame building process utilizes dedicated fixtures to hold the individual tubing components in specific orientation so that they can be precision machined and shaped. We have fixtures made in-house, by Cobra, Farr, and (defunct) Anvil. The tooling industry is definitely growing; Joe (Cobra) and Todd (Farr) are experienced builders themselves, making some slick tools for builders.

Once the tubes are shaped, they go through a rigorous mechanical, ultrasonic, and chemical cleaning cycle to ensure they are free of anything that could contaminate the welds; titanium awesome material and hella strong but notoriously susceptible to cracking if the parts are dirty when welded. The tell-tale evidence of sub-par cleaning is a brown haze around finished Ti welds.

The fabrication process from this stage on is “white glove” clean. The machined tubes are set in a dedicated fixture that ensures alignment and the desired geometry. Argon gas is pumped through the whole assembly to remove oxygen from the inside. The joints are tack-welded in sequence and alignment is checked again. We then take the frame out of the fixture and stick heat sinks in the head tube, BB, seat tube, and dropouts to minimize distortion from welding. The frame is held in a special fixture, think of a heavy bike work stand (i.e. EVT’s stand) that is lower to the ground so that it can be spun around and you can weld while seated. Good welding requires zen-like focus and a steady hand, so the ability to constantly adjust position as you work around the joint is critical.

Once all of the joints are welded, the frame is prepped. All of the mounting points are machined with special tooling to ensure the headset, seat tube, bottom bracket and axle interfaces are spot-on. We then apply graphics with an anodization process. I prefer anodizing titanium over painting because it's quick and can be changed easily down the road if the rider wants to update graphics or colors.

Is this frame 24" wheel specific? What is the geometry?

This frame is designed around 24” wheels and a 26” fork. I’m not confident the 24” fork offerings can handle the abuse of dirt jumping and park riding. The axle-to-crown dimensions on 26” forks are almost identical, so it was pretty easy to build around forks like the Pike and Marz DJ. The frame’s geometry is designed for tricking and to maintain momentum – the back end is slammed at 345mm, 74* seat tube, 69* head angle, 385mm reach, 560mm stack, and 15mm of bottom bracket drop. We massaged the bottom bracket and head tube junctions to make the geometry work without doing silly things like bending the seat tube or crushing the [chain]stays for tire clearance.

I noticed there are some short Hope Kids cranks and an oval chainring. Can you explain that unusual choice for a single-speed setup?

24”-wheeled dirt jumpers require some creativity to produce a bike that rides like their 26” big brother and suits a much lighter athlete. If you think about it, the average 24” rider is about 50% lighter than their 26-slinging counterpart but only 15% less in height. The 24" bike needs to be significantly lighter for the rider to have good control, yet only slightly smaller. Most junior cranks are tanks or noodles... enter Hope crankset. Hope makes these mid-sized EVO cranks for their Academy [a cool program to help kids get on proper fitting and performing bikes]. The crank and oval chainring are maximizing energy transfer to the wheel having minimal flex, and a stiff 30mm axle. The oval is somewhat unconventional for a DJ, unless you are Matt Jones, but we wanted to test the “+2 teeth” theory and have some fun with it. Cranks are 150mm, which allows for bar spins without clipping the pedals; we’ve seen a few 24s that suffer that issue.

Can you run us through some of the other components that make this a unique build?

I mentioned the Paragon headtube, which we modified with gyro tabs, and we positioned the gyro down over the headtube to have plenty of throw on the brake without hitting the stem (a common problem on retrofitted frames). The chainstays connect to the BB through a sculpted “yoke”, which is a single-piece 3D-printed from Titanium. It’s shaped to give clearance for the 2.2” tire and 32T chainring while increasing stiffness. This was our first test of additive manufacturing, and it came out tight. 24” custom carbon rims were paired with Hydra hubs. We also went with a hydraulic caliper to recoup stopping power sacrificed by the gyro.

What other frames or projects are you building on the bike side of things?

The 24" chainstay yoke got us thinking about how additive manufacturing could be used to further reduce fabrication time, improve strength in common failure points of full-size DJ frames, and increase design flexibility to make a readily customizable frame. By using additive, we invested the design time once and saved a bunch of fab time on all future frames. For this project, we doubled our engineering team, added an industrial designer, and we’re partnering with some awesome athletes for real-world testing and design feedback.

What does the future hold for Darwin Designs?

Following the success of our additive DJ project, we’re going to apply the concepts to our full-suspension trail bike design. Additive technology is evolving rapidly and the cost dropping at an equal rate. We want to push this technology as far as possible to make a better bike for ourselves and our athletes. I’d also love to justify an in-house EOS Ti printer… I just need to figure out how to print bikes from the trailhead.

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Reviews and Tech Bike Checks Dirtjump Bikes Darwin Designs