Built to last: One emerging bike brand’s quest for more durable carbon fiber

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Jen Hanna is the director of business development for Innegra Technologies, a company in Greenville, South Carolina whose entire existence relies on getting other companies to incorporate its unique unique impact-resistant and energy-absorbing polypropylene fiber into their own composite structures. So when Hanna decided to try and get into the cycling world, one might assume that a major player like Trek, Specialized, or Giant would be the likely candidate for a partnership. Not only would any of them have the technical resources to make such a marriage possible, but they’d also carry the largest audiences who could benefit from the increased durability. Yet Innegra has now entered an exclusive development partnership with upstart American manufacturer HIA Velo, whose target production for 2017 is around 1,500 units — less than those A-level companies sometimes sell in one size of a single bicycle model. As is often the case, though, the numbers don’t tell the whole story.

Hitting stuff with hammers

Laid out on a table before me during a recent visit to HIA Velo’s headquarters in Little Rock, Arkansas, were two carbon fiber main tubes: one reinforced with Innegra, the other without. Also sitting next to them was a full-sized framing hammer. I gleefully obliged when directed to hit both tubes with the hammer as hard as I wished.

As expected, the hammer barreled through the standard carbon-fiber tube, visibly and audibly shattering however many layers of material comprised its thin walls. Little of its original stiffness remained; I could press my thumb down into the mortally wounded area, and the entire tube easily bent in my hands.

I hit both of these carbon fiber frame tubes with a framing hammer – hard. The standard tube on the right shattered upon impact, with little remaining structural integrity. The Innegra-reinforced one on the left was still damaged, but much less so.

The first indication that something was different with the Innegra-reinforced tube was how the hammer rebounded upon impact. The tube was still visibly damaged, but the rebound suggested that it didn’t absorb as much energy as the unreinforced tube. Instead, it seemed to slough off the hit, at least partially. And though I could still press my finger down into the spot where I hit the tube, it wasn’t nearly as easy to push down, the affected area was much smaller, and the tube itself still seemed surprisingly stout.

To clarify, Innegra isn’t touting its polypropylene product as some sort of indestructible armor for carbon fiber, but more of a safety mechanism — a sort of parachute, if you will — to keep you from tumbling to the ground in the event something happens to the plane.

Hanna draws an analogy to the whitewater kayaking market, where Innegra is used to reinforce the composite shafts and blades of paddles.

“They really market it as a safety feature to get you home that day,” she explained. “If you receive damage, or you get the shaft, the paddle blade, stuck between two rocks, and you get a crack, you’ll be able to safely get home, but you still probably need to buy a new one.

“You spent a lot of money buying a carbon bike, and you want some added protection in there, and that’s what Innegra does,” she continued. “A little bit can go a long way to enhance a carbon-fiber structure by protecting those carbon fibers. So your carbon fiber’s going to carry your strength and your structure; the Innegra adds the toughness for those fibers. It’s a protection layer for those fibers.”

Innegra can make it harder to damage carbon tubes in the first place, and it helps those tubes maintain more structural integrity after a critical blow.

In fairness, the hammer experiment was hardly a scientific test, but more of a neat visual indication of Innegra’s capabilities. HIA Velo is already working on developing an impact test protocol for its in-house lab, but currently, neither company offers up any hard data on exactly how much the addition of Innegra improves impact resistance and damage tolerance. Regardless, the results are encouraging.

HIA Velo is reinforcing the top tubes, seatstays, and fork with Innegra fibers on both the Alfa and Alfa All Road models.

The convenience of in-house manufacturing

HIA Velo proudly touts its made-in-America roots, but the ultimate value of its business model is not where it’s located; it’s that everything is done in-house, from design straight through to fiber lay-up, molding and curing, paint, and assembly. Certain operations, such as infusing fiber plies with resin and some CNC machining work, are done elsewhere in the U.S. But by and large, all of the key operations happen under one roof.

That sort of arrangement is exceedingly rare in the modern carbon-fiber bicycle industry, and it’s that confluence of factors that ultimately led HIA Velo and Innegra Technologies to join forces, not production volumes.

Hanna admits that a small company like HIA Velo wasn’t the first to come to mind when she first set out to enter the bicycle market. Indeed, she was initially after the major manufacturers, and she and her team had tried for years to get a major brand to use its fibers, to no avail. At seemingly every turn, Hanna would run into roadblocks: either no one seemed overly enthused to invest the time to figure out how to best use the material, or the third-party Asian factories used by most bicycle companies wouldn’t grant Innegra’s engineers sufficient access to their facilities and processes to provide any meaningful engineering support.

Real-world benefits or not, it looked as though pursuing the bicycle market would be a dead end for Innegra.

“We had been chasing companies in the cycling industry for three years,” Hanna said. “A lot of times, the conversations ended when factories wanted to pre-preg or make their own material out of the fiber and they had challenges and wouldn’t let us into the factories or wouldn’t give us enough information to help them overcome whatever hurdles they were running into.”

Those difficulties are hardly trivial. Among the potential issues are surface “fuzziness,” which makes it impossible to get a clean and glossy finish, and poor bonding with surrounding carbon fiber layers, which introduces a failure-prone shear layer that can make a structure substantially weaker, not stronger.

“With Innegra being a more ductile [pliable] material, you are going to affect your mechanical properties,” Hanna explained. “So if it’s not done properly, you can can a significantly worse part and not see the benefits.”

HIA Velo’s small initial target production volumes and (so far) limited name recognition make it an odd choice in business partners for a composites company looking to expand into the cycling market on a mass scale. Instead, it’s HIA Velo’s unique way of designing, engineering, and manufacturing its frames that make for an ideal pairing.

Hanna’s doggedness would eventually pay off, though perhaps not as she originally envisioned. Early collaborations with Specialized may have failed to bear fruit, but two of the engineers there — Sam Pickman and Chris Meertens — would eventually form the backbone of HIA Velo’s nascent composites program.

“I had worked with those guys at their previous positions,” said Hanna. “They wanted to use the product, but they struggled in Asia to get it in. They already knew what they wanted to do coming into their first day [at HIA Velo]. They came to us pretty quickly.”

“We’re trying to build products that people ride forever,” said Pickman. “That’s our goal. We want to make sort of lifelong products. Chris was basically like, ‘You know what? Innegra could be perfect for us.’ It just integrated really seamlessly.”

According to Hanna, several factors led to the somewhat unlikely pairing between the two companies. HIA Velo’s relative proximity to both Innegra Technologies and Axiom Materials — which supplies the raw pre-preg composite materials — certainly helped in terms of getting people face-to-face, and there was that pre-existing interest in the material from Pickman and Meertens. But it was HIA Velo’s vertically integrated production that ultimately created an ideal formula.

Because HIA Velo’s carbon frames are made just a few steps away from where the engineers are designing them, any changes to the lay-up can be put into place in hours, not weeks.

Innegra Technologies sent its own composites engineer, Russ Emanis, to HIA Velo to assist Pickman and Meertens in person, with assistance from Axiom in providing sample materials.

With all the necessary tools readily at hand, the trio went through countless experimental variations in just a few days, laying up materials themselves, cooking the molds minutes later, and then walking the samples a few steps down the hall to the company’s in-house test lab to validate changes.

In a more typical modern manufacturing arrangement, such a process could have taken months, but with Emanis’s help, Pickman and Meertens were able to go from those initial trials to near-final lay-up schedules in just six weeks.

Many of those lay-up variations were on hand during my visit: some with Innegra-infused spread-tow surface layers (similar to the TeXtreme materials used by Felt Bicycles), others with Innegra incorporated beneath the surface, and still others with more finely woven finishes. While the hammer experiment provided a fun hands-on representation of what Innegra can potentially do, the variety of trial tubes visually indicated how much work was required to figure out how to use it.

“When the rep is a three-hour drive away and he’s willing to come up and lay out parts with you,” said Pickman, “that’s a big deal.”

“The processing of Innegra is different,” Hanna added. “You see the fuzzing, you see the fact that it’s hydrophobic, that it’s not compatible with every resin. It’s a different beast. So there is a lot of trial and error to it, and if we can help shorten that cycle time, I think that’s beneficial.”

All the eggs in one basket

HIA Velo — under its new Allied Cycle Works brand name — is launching its new Innegra-infused composites knowhow on two new road platforms: the Alfa road racer with rim brakes, open quick-release dropouts, and more traditional tire clearances; and the Alfa All-Road, which features flat-mount disc brakes, thru-axle dropouts, and room for higher-volume rubber.

Both will incorporate Innegra in the top tubes and seatstays — the two areas most prone to damage on a carbon-fiber road frame — and the matching made-in-house carbon forks will get Innegra reinforcement in the crown and lower steerer tube areas — again, the most common spot for damage in a crash.

Whether either (or both) of those bikes ends up being a commercial success still remains to be seen, as neither will be widely available for a few more weeks. And while the addition of Innegra fibers supposedly won’t have much of an effect on either bike’s stiffness or ride characteristics, it remains to be seen how these uniquely reinforced frames will feel out on the road.

The promise of top-shelf performance with increased durability will undoubtedly resonate with many potential buyers, though, as will the surprisingly reasonable US$2,700 frameset cost for a truly made-in-USA product. Either way, Innegra Technologies is putting so much faith in the partnership that it put in place a two-year exclusive agreement with HIA Velo, forgoing potential volume with another brand in the meantime. The agreement doesn’t preclude someone from using Innegra, but it does prevent the company from lending any on-site engineering support to help with the process.

Either way, Innegra Technologies is putting so much faith in the partnership that it put in place a two-year exclusive agreement with HIA Velo, forgoing potential volume with another brand in the meantime. The agreement doesn’t preclude someone from using Innegra, but it does prevent the company from lending any on-site engineering support to help with the process.

“Right now, the way the agreement is written, it does not exclude anyone from using Innegra,” Hanna said. “It just excludes sending Russ into their factory to help them. So they can still use the product and try to figure it out.

“The landscape changes now because you can’t say, ‘It doesn’t work’,” she continued. “When you have a company already using it and showing that it has benefits, an engineer can’t go back to their boss and say, ‘I tried it and it doesn’t work.’ That’s not really going to fly anymore. So just the proof of concept is number one, and moving forward, after our agreement expires, that just opens up the opportunity to be able to work with and help them develop. If that requires travel, then we travel, and if that requires getting access to some of those factories, that’s really up to the brand and what their factory allows them to do. Ultimately, that will help us develop more of a market in other areas.”

Time will tell if Hanna’s bet pays off. If the Alfa and Alfa All-Road debuts go well, Allied plans to expand the concept into a yet-to-be-announced range of carbon fiber mountain and ‘cross bikes, too — and it stands to reason that other companies won’t want to let the little company from Little Rock, Arkansas, own the exclusive for long.

“We’re not gonna be the only people doing this; we’re just the first,” said Meertens. “So we better get going, you know?”

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