“Hi, this is Chris, I’m returning your call.” These were the opening words from a phone call that kick-started the building of Aaron Humphrey’s new custom Slim Chance. The “Chris” on the other end of the phone line was Chris Chance, a legend in the world of bicycle framebuilding, the man behind the iconic Fat City Cycles that graced the pages of mountain biking magazines throughout the 1980s and 90s and made the builder synonymous with beautiful bikes known for their exceptional ride quality.
Humphrey originally approached Chance for a bike project that he had in the making – a custom Slim Chance made to recall a beloved road bike of his, in a modern form. Despite opting for a stock frame geometry, he wasn’t just looking to add another bike to his collection; he was chasing a feeling he had found in a vintage rim-brake Ibis Spanky, updated with current touches and technology like disc brakes.
Chance took on the project, and months later, that casual initial phone call took shape in the form of a custom Fat Chance Slim Chance, a bike crafted not for racing or A-to-B transportation, but the pure joy of riding. Here’s how Humphrey’s Slim Chance came to be.
From Spanky to Slim
With the Slim, Humphrey was chasing a perfect blend of responsiveness and comfort, and bring it to life in a modern steel frame – and it turned out he didn’t have to go full-custom to get that. The Slim Chance – a road bike Chance makes under his new brand name “Fat Chance“ – with its classic lineage as one of the first TIG-welded road bikes and a stock geometry that almost perfectly mirrored his beloved Spanky was to be the canvas for this ambitious project.
“The Spanky floats a bit, flexes a lot, and delivers a smooth, predictable, quick, and silky ride,“ Humphrey says. “It sets an extremely high bar in ride quality.” But Humphrey wanted something more – and he was willing to put in the work to make it happen.
“I selected the Slim because its stock geometry was nearly identical to the Spanky,” he says. “Only the chainstay length (2 mm) and the slope of the top tube were different, the stack and reach (560/399 mm vs 571/396 mm) were nearly the same. The difference in stack is due a shorter head tube on the Spanky, quill stem, and locknut, but the bar center [height] is effectively identical. Similarly, the head and seat tube angles were the same, and the trail only varied by 1 mm. If I was going to get an update on the Spanky, these numbers were it. On paper, the contact points fell within 1-2 mm of each other, so the Slim was as close as one could realistically expect.”
Following that call back from Chris Chance himself was a collaboration that went beyond the typical bike-building process. Humphrey, with his meticulous eye for detail and a passion bordering on obsession, dove headfirst into the world of frame design, poring over geometry charts and even venturing into the world of 3D computer modeling to understand how different tube combinations would translate to real-world ride characteristics.
From vision to reality – collaborating with Chance
Humphrey envisioned the Slim as a modernized version of his Spanky, complete with carefully chosen upgrades like Paragon UDH dropouts for future flexibility. “At this time, there is no Transmission-style road derailleur, but the writing is on the wall. UDH offers more flexibility if SRAM expands Transmission to the road world,“ he explains. “It’s clear that SRAM is heavily invested in using this mount in the future. Even though the gruppo I have on hand is standard, using this hanger allows more flexibility in the future if SRAM expands Transmission to the paved world.”
“Other than the tube combination and coupler, the modifications I requested were minimal: bosses under the top tube for a possible bolt-on top tube bag, something I have found to be invaluable on other bikes, especially for epic days and travel. I also asked [Chance] to put a boss on the seat stay bridge as a location to mount a tail light. The geometry was such a perfect match that there was no reason to change anything. Chris suggested using a particular seat tube he had on hand, a stainless tube that had longer butting and would be very strong for the coupled seat tube. I quickly agreed to this.”
The obsessive attention to details resulted in a bike that is as much a work of art as it is a high-performance machine, and its colour is the finishing touch. The frame is draped in an aqua fade paint job that transitions seamlessly from one shade to the next, and many parts are colour-matched.
“The 90s may have been Peak Ano in the mountain bike world, while the 2000s swung back to basic black. I’m a pretty big fan of colored bits and bobs, so things like anodized blue brakes, blue disc lockrings, and even (gasp) colored bar tape make an appearance,” Humphrey says. “I sent two stems to Chris to include in the painting for even more matchy-matchy. You can’t do colored bits half-assed – you must go all-in.”
Details like the anodised Eddy logo – the iconic Fat Chance mascot – subtly placed on the seat post, pay homage to the brand’s legacy, while modern touches like the Fidlock magnetic mounts and Hope RX-4+ disc brakes blend with the classic lines of the steel frame.
Little doodles adorn the bike elsewhere too; the one on the fork has a special story.
“The story behind the ‘cowboy up, cupcake’ sticker on the fork is from a long time ago when I was a ski racing official,” Humphrey says. “I printed a bunch of stickers about 20 years ago and they made it literally around the world; one is on Jacquie Phelan’s banjo. I have no idea how she got it but it’s awesome that a hero/pioneer of mtb has my sticker.”
The bike is rolling on Nextie rims and Onyx hubs – Humphrey built the wheels himself with Sapim bladed spokes and DT Pro-lock brass nipples. Humphrey admits that the Onyx hubs aren’t known for being light, especially the rear, which weighs in at over 100 grams more than most road hubs. But what they lack in weight savings, they more than make up for in performance: instant engagement, silent coasting, and a custom powder-coated green finish that pairs beautifully with the aqua fade.
And then there was the Z-coupler from Santana/Paragon Machine Works. Humphrey initially specced this out at 75 mm, hoping to squeeze a bit more stiffness out of the frame. When building the bike, Chance shortened this to 41mm to make it work for the frame. Since getting the bike built up, Humphrey has taken the Slim apart and packed it for travel, and this part of the bike has worked wonders in making that easier.
“I’ve been exceptionally pleased with the S&S couplers on my other bikes, but the Z-coupler is a whole new level. The diminutive size and unbelievably simple and clever design notwithstanding, it just works. It’s fast, easy, intuitive, and zips together with a single bolt. It’s genius. It’s also fantastically expensive, but like the good things, you get what you pay for. In reality, the cost of an S&S coupler vs a Z-coupler is pretty much a wash, and the function of both is identical, but in a new build, the Z is a much better choice.”
The Slim Chance on the road
But the true measure of any bike is in the ride, and the Slim Chance didn’t disappoint. Humphrey, after months of anticipation, describes the ride as nothing short of wonderful.
“As I dial it in, I get happier with it. Although the Spanky will need to be pried from my cold, dead hands, the Slim has proven itself to be a steel disc road bike for the modern era.”
The Slim, for Humphrey, is a bike that manages to be both smooth and lively, rolling over rough pavement yet surging forward with every push of the pedals. He says the lack of lateral flex, thanks to the carefully chosen tube combinations and attention to detail during the building process provides a confidence-inspiring stability, while the overall compliance gives the bike a supple feel that distinguishes it from the often-harsh ride of modern carbon frames.
Comparing it to his benchmark Spanky, Humphrey describes the Slim Chance as a slightly different but equally rewarding ride. The Spanky, with its smaller tube diameters and quick-release hubs, has a more pronounced “float“ and a quicker turn-in, while the Slim Chance feels more planted and carves a wider arc through corners. It’s a difference most noticeable in the way the bikes handle tight turns.
“The Spanky seems to turn more quickly. I’ve double-checked the trail, fork offset, and head tube angle numbers over and over, and both bikegeocalc and yojiming show [trail] at 54 and 55 mm,” Humphrey observes. “The Slim tracks a bit longer in a turn, but feels like it carves better. In ski parlance, the Spanky turns like a slalom ski, and the Slim turns like a quick GS ski (perhaps a skiercross ski?).”
The final chapter
This Slim Chance seems like a prime example of collaboration between a passionate bike owner and a master bike craftsman. If you read through Humphrey’s post about the build process, you’ll also become familiar with many of the hurdles the months-long process of creating a hand-built bike entailed – even if you go for a stock geometry frame.
“If you consider a custom frame (and you absolutely should), research the bejeezus out of other bikes, test bikes, get a good fit, and pay extremely close attention to details,” Humphrey advises. “Choices like fender or rack mounts, couplers, dynamo routing, and so forth can make or break a new bike – even if it’s exactly what you ordered, if you’re OCD about your machines, a tiny thing can bug you, so be patient and do your homework. A framebuilder with the experience that Chris has can help make sure that you get the bike of your dreams.”
For Humphrey, the Slim Chance was a passion project – one that started and finished in a memorable way.
“The final chapter was when Chris invited me to show it at the MADE show in Portland. We spent three days hanging out, chatting, and being unfettered bike geeks,” Humphrey says.
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