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by James Huang
August 20, 2016
Photography by James Huang
TECH NEWS BROUGHT TO YOU BY BIKEEXCHANGE
The 1992 Olympic Games had just finished, and USA Cycling, together with a group of top industry partners, embarked on an ambitious mission to provide its track athletes with the fastest bike in the world in time for the 1996 Atlanta Games. The so-called GT Superbike was a wild departure from conventional design of the time — a full-blown ground-up rethink of what a bike could be. But while the engineers were looking to the future, the UCI was more interested in tradition, and the course of bicycle engineering from that point forward would be forever altered.
By any stretch of the imagination, the Project ’96 GT Superbike was an incredible design. Born from the idea of making the fastest bike in the world, its makers were free from the restrictions of any technical regulations, and they took full liberty with the freedom that provided.
To more efficiently slice through the air, the futuristic carbon fiber composite frame used airfoil cross-sections throughout, and the top tube and seatstays were omitted completely. The bike was also impossibly narrow from tip to tail, as well as curiously low and short, with a conventional 700c rear wheel but a tiny 24in front wheel that allowed team riders to follow each other more closely and enhance drafting effects.
Everything about the GT Superbike 2 is incredibly narrow.
Such wholesale abandonment of convention required a systemic approach to the rest of the bike as well. Virtually everything had to be custom-built specifically for the project. Component partner Mavic developed special wheels and cranks to match the frameset’s ultra-narrow profile, and every cockpit was a bespoke creation for each individual rider. The integrated seatmasts were essentially non-adjustable, too, and whatever minute changes were possible were arduous and slow.
But the bike was fast. Perhaps too fast.
GT Bicycles was an industry icon in the mid-1990s, but only in the realms of mountain biking and BMX. Although road cycling was a potentially lucrative segment, the company had virtually no credibility away from the dirt. GT founder Richard Long wanted to change that, and felt a high-visibility appearance at the Olympics would go a long way towards establishing a reputation in the road world.
“It was very soon after the Barcelona Olympics, in early 1993, Richard said, ‘Hey, these guys from USA Cycling are going to come up and look at the place. We’re kicking around this idea of sponsoring the team’,” recounted Forrest Yelverton, GT’s head of engineering at the time. “So these guys from USAC came up, they saw what we did there, and we chatted about the possibility of doing this. As manufacturers, the guys at the shop were totally stoked to be able to do such a thing. Shortly after that, those guys inked a deal and we started on this long parade to make this ‘ultimate bike’ for 1996.”
From head-on, the bike virtually disappears. The head tube, for example, is just 26mm wide from top to bottom — half as wide as a modern carbon frame. Grab a ruler to see for yourself just how incredibly narrow that is.
The idea of creating an “ultimate bike” sounded good on paper, but actually figuring out what it would entail was challenging, to say the least. How does “ultimate” translate in terms of performance? What would it look like? How would it be built?
It wasn’t long before the key individuals were gathered for Project ’96: Yelverton and his team at GT’s facility in Colorado, GT composites engineer Ralph Ray in California, aerodynamics guru Chester Kyle, and composites specialist Don Guichard.
Legendary bicycle composites pioneer Brent Trimble machined the frame tooling at his home in Boulder, Colorado. Outside partners included French wheel and component company Mavic, and American data specialists EDS out of Texas.
GT had no experience with track bikes at the time, so the company first built a number of steel framesets, both to decide on geometry, and to help the athletes grow acquainted with being sponsored by what, at the time, was a mountain-bike company.
Once that was settled, GT then transitioned to a series of aluminum bikes made from aero-section extrusions — internally known as “Superbike 1”. As advanced as the SB1 bikes were for the day, that was still just a stopgap measure. The final product would be much, much more radical.
Without the structural support of seatstays, the chainstays had to be massively overbuilt. Even so, they measured less than 12mm at their thickest point, and less than 8mm at their thinnest.
“I do remember at one of the meetings, just everyone around the chalkboard, and someone saying, ‘We could go like this, we could go like that, with carbon we don’t need this tube, we don’t need that tube’ — it was all sort of a group discussion about the options,” said Yelverton. “It all just sort of narrowed down to this one being the best from a combination of aerodynamics, ultimate stiffness that the rider was going to need, and manufacturability. We considered getting rid of the down tube, or getting rid of the top tube, or getting rid of one or the other stays — there were a lot of things being batted around, and this just melted out of that group’s discussion about what was going to be the best way to go about it.
“We had three main [concepts], and from those, we built these clay and steel and styrofoam models that we ran at the tunnel.”
Building those models was a project in and of itself. Today, designs are more readily translated off the computer screen, but twenty years ago, it wasn’t so simple.
The seat tube cutout shields nearly the entire height of the rear wheel, even extending down below the bottom bracket shell.
Today, Jeff Soucek is R&D director at Felt Bicycles, but in 1993, he was GT’s senior industrial designer, a self-described “grunt” responsible for turning those drawings into physical models. And conveniently, he was into model airplanes.
“I had been doing slope soaring gliders at the time with my brother, and we would scratch-build all of our own airplanes,” he said. “So I built it like an airplane wing. I had Forrest give me a horizontal cross-section in one-inch increments from top to bottom. So then I would take that cross-section, glue it to a small piece of plywood, cut out that cross-section, top and bottom, glue it to a piece of foam, and then use a hot wire cutter and trace around both those cross-sections to make a loft, inch by inch.
“So after I did all those lofts, inch by inch, to make the entire bike, I then skinned it with balsa and fiberglass — just like you would on a slope soaring glider — and then from there, we built these prototype composite molds off of it. We basically took the frame, we built a shadow box around it, and backfilled it with aluminum-filled epoxy.
The project consortium actually had three final concepts in mind, but this was the one that tested fastest in the wind tunnel.
“As far as the materials goes, that’s where Don Guichard came in. He got his hands on some outdated satellite material that had a really high modulus, and that’s what we built it out of. We basically laid it up and built it in the back of GT. That was the first prototype. The production bikes were obviously made differently, out of aluminum molds, but the first prototype was made that way.”
Testing for the new carbon fiber version — internally dubbed Superbike 2 — was done in secret at the U.S. Olympic Training Center Velodrome in Colorado Springs, Colorado. One of the testers was former professional cyclist Christian Vande Velde, a teenager at the time and resident athlete.
“When we first rode it, we were so excited,” Vande Velde told CyclingTips. “It was in Colorado Springs before we went to Atlanta. The biggest thing with that bike was the Q-factor. It was very, very narrow — maybe the narrowest ever produced. Most of us were young enough that our bodies were still malleable but it was easy to adjust. I loved it from the get-go. It was easy to ride, obviously the 24in front wheel was kind of funky, but then again, that’s all we knew.
The 24-inch front wheel let riders draft each other more closely in team events.
“It was a pretty sick bike,” he continued. “The best thing was that nothing ever had to be changed; the bike was yours and yours alone. I trained on that bike so much that I felt more comfortable on that than I did on my road bike. It was just a part of me. That was one of my favorite bikes that I’ve ever ridden in my entire life.”
Vande Velde was a team alternate at the Atlanta Games in 1996 so he didn’t actually use the bike in competition at the Olympics. However, he raced on it regularly in the three years afterward, on both the national and international circuits.
“I won a couple of titles on that bike: the pursuit in ’97, and the World Cup overall on that bike in ’97. I have maybe more [time on this bike] than anyone. We rode those all the way through the Worlds in 1999.The teams changed around a lot but ’96, ’97, and then ’99 — I rode that thing quite a bit. No one rides a bike for four years now.”
The U.S. track cycling team raced the Superbike 2 to limited success at the Atlanta Games, with Erin Hartwell bringing home a silver medal in the kilo. Sadly, Richard Long didn’t even get to see that happen after so much time and energy invested in the project; he was killed in a motorcycle accident just days before the opening ceremonies.
The Superbike 2 would continue to be used in competition for three years after the Games. Race results notwithstanding, it was a success from an engineering standpoint as it unquestionably provided a technological advantage to its riders. Yelverton says that GT had the wind tunnel data to prove that it was faster than other bikes at the time.
“I don’t remember the numbers, but it was significant,” he said.
Is it a bike or an airplane? Such was the thought of then-UCI president Hein Verbruggen when seeing the Superbike 2 for himself. Such designs were banned shortly thereafter.
Given that advantage, it’s difficult to say just how much longer the GT Superbike 2 would have been ridden, or if there would have been subsequent Superbike editions to follow.
Unfortunately for GT and other similarly innovation-minded companies, though, the UCI set out to squelch those technological advantages shortly after the Superbike 2 broke ground in Atlanta. The GT certainly wasn’t the first bike to sport a decidedly unconventional layout (the Lotus 108 preceded it by a substantial margin, for example), but it may have been the proverbial straw that broke the camel’s back. The now-infamous Lugano Charter was drafted later in 1996, and then finally went into effect in 2000. From that point forward, designers and engineers were dramatically restricted in terms of what they could and could not do.
“[The Superbike] just pushed it too far,” said Soucek, “so that’s when we they had the charter come up and it introduced all the current regulations on the bikes now. The 3-to-1 rules, the boxes, double diamond frames, and all this lovely stuff we deal with today is kind of a result of that project.”
“I remember, at the Olympics, seeing [UCI president Hein] Verbruggen in this little sectioned-off part of the stands with no one around him over there looking at the bike,” said Yelverton. “And then it was shortly after that, sure enough, we started seeing in print, ‘I thought I was looking at airplanes; this is crazy! Mano y mano, I’m going to stop this now.’ We fought that hard, of course, but we lost.”
The incredibly narrow bottom bracket brought the pedal stance width (better known as Q-factor) down to around 100mm – roughly 40mm narrower than typical track cranks.
We can only imagine what bikes today might look like had that fateful document never been adopted into the UCI rulebook, but given where the industry was headed in the mid-1990s, it’s safe to say that modern machinery would be vastly different from what we have currently.
“You can kind of look at bikes that you’re seeing in Ironman triathlon,” Yelverton said. “They’re pretty similar; they just have some bigger sections, and some other weird things going on, but I think, had the openness of the design rules been allowed to be out there, we’d be seeing some crazy stuff right now.”
Sadly, the GT Superbike 2 now merely stands as a testament for what could have been, and Yelverton looks back fondly at what might otherwise have been viewed as the dawn of a new era in terms of bicycle technology had the UCI not intervened.
“I have a picture of [the Superbike] hanging on my wall, right now. I definitely have a soft spot for it. It was a cool bike.”
The GT Superbike 2 was one of the last — and perhaps best known — race bikes that fully capitalized on the lack of design restrictions in the mid-1990s.
Cockpits were custom built for each rider out of extruded aluminum.
Aerodynamic efficiency was still a fairly new concept in the cycling industry, and engineers commonly borrowed airfoil profiles from the aerospace world.
A bolt extends up through from the bottom of the steerer tube, and attaches to the extruded aluminum handlebar assembly with a wedge. In many ways, it’s like an upside-down quill stem.
The custom-made cockpits allowed for some adjustability, but not much.
Rotating the bar helps reveal the ultra-narrow profile of the frame.
Engineers didn’t want to make the head tube wider to accommodate conventional headset bearings. Instead, the fork’s steel steerer tube rotated directly on bushings that were pressed into the head tube. It wasn’t an optimal system, but it worked.
Standard rear track frames measure 120mm between the dropouts. This one is less than 60mm.
The dropouts feature partially recessed hardware for a cleaner profile. The dropouts and axle ends were also keyed together for more precise fit.
The Selle San Marco Strada saddle had to be modified in order to attach to the integrated seatmast. Adjustments were tedious, to say the least.
The fork looks like it’s made of carbon fiber, but it’s actually steel. Automotive body filler was used in some areas to help build up the shape, particularly around the crown.
The aero extensions were fixed in place with internal wedge-style clamps. Bolts were accessed from the front.
The custom-made 24in Mavic front hub was just 50mm-wide, half the width of a standard front track hub.
Flat-head mounting hardware maintained the fork’s speedy profile.
Grip tape was applied where riders would hold on to the base bar. This area was only used for starts, though, so it was more important to make it fast rather than ergonomic.
Mavic provided wheels for the GT Superbike project, including flat rear discs and a variety of different front wheels.
This engineering prototype was fitted with a variety of different pieces of equipment that the development team was evaluating. These Swiss-made CAT carbon cranks weren’t used by the American team at the Olympics, and the FSA chainring somehow made its way here later on.
The 19mm-wide Continental track tubulars are badly dry rotted now, but they were race-ready 20 years ago.