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by James Huang
December 20, 2019
Photography by James Huang
For performance-minded road riders, the default bike of choice would seem to be made of carbon fiber, be aerodynamically shaped, and be fitted with disc brakes. It’s the direction everything is headed, after all, and where the lion’s share of R&D money is being spent.
But Tom Anhalt is not like most performance-minded riders.
In many ways, Anhalt is sort of the stereotypical American enthusiast. He’s middle-aged, but rides a lot. He’s a mechanical engineer in the medical device field. He’s highly active in the Southern California road scene, and owns several bikes. And if you’re embedded in the small online community that is obsessed with bicycle aerodynamics, he’s somewhat of an internet legend.
It should therefore come as no surprise that Anhalt was the proud owner of one of the most aerodynamically efficient road bikes of its time, a first-generation Cervelo S5 — that is, until someone stole it out of his garage.
Like any cyclist in that situation, Anhalt quickly got to thinking about what bike would replace that sadly lost steed. Surely another sleek carbon creation would take its place, no? No.
You see, while Anhalt was contemplating his options, he resurrected his old steel Bianchi as a temporary stand-in, updating it with modern aero wheels and fast-rolling tires. And although it was decidedly heavy, it also rode brilliantly.
And so he got to thinking.
“Cervelo had come out with their second-generation by that time [my bike was stolen], and I was really close to pulling the trigger on just getting another S5,” Anhalt explained. “But then I was riding around on an old 1986 steel Bianchi that I still have, and I had these HED Jet wheels still, and I put a good set of wheels on there and a nice set of tires, and that bike was not slow.
“It’s a 30-some-year-old bike and I’m keeping up on group rides because I have good tires and good wheels. The only time I’d slow down — the thing weighs 22 pounds (10 kg) — is when you start going uphill. So I went, ‘gosh, I would either spend $5,000 on a carbon S5 frameset, or for less money, I could have a custom bike, done the way I want to do it, and try some things I want to try.’ The appeal there is that it was something that I could collaborate on and come up with something unique.”
Anhalt’s craftsman of choice was local builder Aaron Stinner.
“Aaron was doing a lot of custom stuff at the time, and I said, ‘hey, can we figure out a way to make an aero steel bike?”
After lots of back-and-forth, the pair ultimately decided on a Columbus Life Air aero down tube (but flipped around from its intended orientation to better work with water bottles), True Temper aero seatstays (in a dropped configuration to reduce the frontal area), and a bi-ovalized top tube (that was originally designed to be a down tube). The rear brake is tucked underneath the chainstays.
Even the cable routing is clever.
“We came up with something to keep everything internal,” Anhalt explained. “We offset the down tube a little bit so there’s a fish mouth at the bottom — I stole that idea from the old Cervelo aluminum bikes. All of the cables route to the bottom of the bottom bracket.
“Aaron came up with this idea of three brass tubes that come down behind the head tube, puncture into the down tube, and then make a slight turn and end. From the top, you can just feed a liner or the brake cable housing into that, and it’ll get into the down tube and then you can get it out the other end at the bottom. If you want to swap cables, you basically just pull them out and push them back in, and they come out where they’re supposed to.
“To cover that up behind [the head tube] you have that nice triad shape with the round head tube, so we just filled that in with body filler. Having the brass tube also made a convenient spot for a pump peg. They weren’t sure if I was serious when I said I wanted a pump peg, so I said ‘if you push back on that, I’m going to ask for a chain keeper, too!'”
Tire clearance is generous, too, with the rear end designed around a 32mm-wide casing, and — after an eventual fork swap — even more room up front.
“We had this idea of this being the one-bike-for-all kind of thing,” Anhalt said. “We specced that the rear triangle should able to accommodate at least a 32 mm tire. The original Cervelo S5 fork could only handle a 24 mm tire, so I replaced that fork with a Whisky No.9 RD+. It’s a rim-brake fork, but it’s designed for longer-reach brakes, and now I can put a bigger tire on the front than the back. I’ve actually test-fit a 36mm in there.
“I use offset pad holders, which give me just enough range to accommodate the longer-reach requirement of the brake with a standard rim-brake [caliper].”
Yes, Anhalt went with rim brakes.
In addition to being a big proponent of aerodynamic efficiency on the road, Anhalt is rather famously skeptical of the benefits of disc brakes for that segment of the market. And to his credit, rim-brake performance is legitimately excellent provided you choose the right combination of components. That’s exactly what he’s done here with a set of HED Jet wheels with textured aluminum sidewalls and carbon fairings (or Boyd Altamont aluminum clinchers for training), SRAM Force hydraulic rim-brake calipers, and good pads.
“I’m still unconvinced. It’s not that I don’t like disc brakes — my gravel bike has disc brakes — but the intent of that was to be able to swap wheels with different tire sizes and all that stuff, and that accommodates that a lot easier than having a set rim-brake,” Anhalt said. “But this is a road bike, and it works perfectly well. I take this up and down some pretty hefty climbs. I’ve never had any issues with this combo. I do agree with disc proponents that braking surfaces should be metallic — there’s something to be said for that.”
Unlike bigger mainstream brands, Stinner didn’t have the benefit of running full-sized models through the wind tunnel, or creating complicated 3D models for computational fluid dynamics simulations. All of this was done on gut, so to speak, but as it turns out, Anhalt has a good feel for this sort of thing.
“I’ve known the Specialized guys, Mark Cote and Chris Yu, for a while,” he said. “Chris emailed me and invited me for a ‘play day’. I brought my bike along and was lucky enough to be able to get some info on it, by itself, with different wheels and tires, as compared to a Venge ViAS, and then with me on it for a couple of runs as well. It did surprisingly well.”
How well, you might ask? Not quite as good as the latest-and-greatest carbon superbikes, but better than one might expect. According to Anhalt, his custom Stinner posted numbers that were roughly equivalent to Specialized’s first-generation Venge, and 10-12 watts slower than the current-generation Venge ViAS when the bikes were tested by themselves — but a less-significant five or six watts when Anhalt is sitting on it.
“Chris said I did a lot of things right with the leading-edge stuff,” Anhalt said. “I had a first-generation S5 fork on it at the time, I had really good wheels, the seatstays are dropped and teardrop-shaped — all this stuff we did with the down tube, all of that stuff helped. As it turns out, they were in the midst of developing the next-generation Tarmac at the time, and [my bike] was pretty close to what they were doing. He was surprised it did as well as it did with the round seat tube and seatpost, because a lot of what they were doing at the time showed that that [D] shape was a little better. Maybe it was some lucky confluence that I got it right.”
One small detail was rather tricky to nail down: the bike’s name. Stinner’s other bike models are named after well-known climbs or roads in the area — Gibraltar, Refugio, Romero — and so this machine needed to somehow fit the mold. As it turned out, the answer was (quite literally) close to home.
“When we started discussing this project, it didn’t have a name,” Anhalt said. “I was going to the shop one day, which is near the airport in Santa Barbara, and I was looking at the street where the shop was on, and the name of the street happens to be Aero Camino. In Spanish, that means ‘aero road’, and I thought that was perfect.”
Nearly 17,000 miles later, that perfection hasn’t faded, either.
Some things are just meant to be.