MATTER OF FACT: Gravel Bike Frame Materials

Welcome to the second of an ongoing stream of posts that share questions I receive from members of the riding community about items of interest to the collective. These posts are primarily about MATTER – the technologies we engage in the act of cycling – but anything and everything related to cycling is fair game, including the stuff I’m definitely not a real expert on, like cognitive science!

This post is the second part of my exchange with Julia, captured in the first installment of the series. I’ve elaborated on a few areas of our conversation here to help the broader readership understand the ideas that underpin the advice I provide.

Holler at me, I’ll run with questions that spark my interest and are likely to do the same for others. Consider the ‘branding,’ MATTER of Fact, a tongue in cheek thing. There are/no facts. Fire away to: teknecycling@gmail.com

My first road and MTB bikes were chromoly, which I loved and now my road bike is carbon, which I love. For a gravel bike I was thinking chromoly, but on my first visit to a bike shop the manager, who does cyclocross racing, said I should get carbon. Any thoughts? Neither of the bikes you suggest [in your response about gravel bike stability] are carbon. I know it can’t be a fast road bike, but I would like something responsive. - Julia

Regarding materials (see this post for another angle on the subject), there are pluses and minuses for every option. I’ve raced at the elite level in mtb, road, gravel and cyclocross on steel, aluminum and carbon. If I was choosing a bike for what you’re looking to do (riding road, gravel, and trails while camping), carbon would be last on my list. Not only is it far more expensive than steel and aluminum, it’s also less suited to loading with gear unless it’s built for that, which isn’t really that common. The sort of falls that a loaded bike will usually encounter will be awkward tip-overs, sideways. That’s the perfect failure mode for a carbon seatstay or toptube.

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It’s not true that carbon will necessarily deliver better performance over a well designed bike in steel or aluminum. Titanium is nicely suited to rough and tumble, but also very expensive, so better for later if/when you determine what your ‘ultimate’ set-up might be (more on this below). 

At this stage I recommend the steel or aluminum route, which would leave you budget for the other stuff that you’ll feel the most: good wheels and tires, good bikepacking gear, proper saddle and clothing. This is the stuff I tend to focus my product tests and reviews on. The shop owner in question might have the typical bias: carbon equals performance. Or, that’s what s/he has in your size. I don’t know, I don’t want to assume too much.

If money is no object, yes, there will be some great options in carbon, but I don’t see it as the place to start. The same applies to titanium. That said, if you do want to head down the carbon path, you will want to focus on the brands that have a strong reputation for very tight quality controls throughout their manufacturing processes. It isn’t particularly hard to produce a strong enough carbon frame that is also fairly heavy, but it is hard, and expensive, to produce carbon frames that are light and strong. This is where the classic ‘light, strong, cheap: pick two’ adage rings true.

If we were sitting around discussing this topic over coffee or during a ride, a few brands would come to mind I’d hone in on. But, given I can’t afford to own more than maybe one or two carbon bikes (and when I say ‘afford’ I mean: afford to replace if I destroy it, or at least repair), I’d say I’d not likely invest in such bikes until/unless I was at the point where I was paring down my stable to a few bikes to focus my budget on.

Bear in mind that carbon repair is actually pretty accessible and not terribly expensive these days, and generally easier and cheaper to have done than metal repair when it comes to tubing damage (see an example of carbon repair pricing here, metal repair pricing here).

So, if I was going to throw down thousands on a carbon frame (the thought pains me…), which companies would I consider?

First, on the very light and performing side, I’d look closely at OPEN and 3T. Both are very carefully manufactured, which is what enables each brand to build their frames light and strong. And expensive. Being really thin, I’d be concerned about wear and tear on these frames; I don’t think I’d expect to get years and years out of them. If a rider tends to be light on their gear, doesn’t crash much, and won’t fly often with the bike (which is scary with thin carbon bikes), such options could make a lot of sense.

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For something more balanced in terms of the durability / price / performance nexus, I’d look at the Lauf True Grit. I rode Benedikt Skulasson’s personal bike with him while in Iceland in 2018, and I loved it. It was also designed and built following close examination of other high end carbon gravel bikes, and Lauf focused on improving on the durability some of them offer.

Naturally, the big brands do carbon well, but I can’t think of one producing a ‘proper’ gravel bike at the moment. (UPDATED) I tested a pre-production carbon platform from Brodie in 2019, which will offers an attractive blend of performance, durability, and affordability. I took the bike to Europe with me in July and rode it over 100 hours in France and Italy. It performed exceptionally well, not least during an odyssey from Nice, France, to Genova, Italy, up and over the mountains! I recommend folks take a close look at the Romax Carbon for 2020.

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On the custom end of the carbon spectrum, I would have to mention Alchemy Bicycles. Each time I read or listen to anything with/about the team at Alchemy that bring their bikes to life I feel more and more confident in their work. Attention to detail, specifically, eliminating voids in the carbon layup process, underpins the ultimate durability of a given frame or component. From what I’ve seen and heard, Alchemy is exceptional in this regard. A high level of attention to detail is always coupled with a lot of time spent on each build, so these frames are necessarily costly.

Circling back to titanium, the material that doesn’t get so much attention these days, I’d point to a few attributes that make the material an excellent choice for a gravel bike, or any bike meant to endure a broad range of stress and rough and tumble.

First, titanium can be built light and responsive, delivering bright ride characteristics like good steel, carbon and aluminum, while also being very resistant to dents and damage from impacts.

The best riding steel frames use really thin tubing, just like the best aluminum and carbon frames. When these bikes are impacted by whatever, from rocks to knees (not joking), they can sustain damage fairly easily. With metal frames visual inspection and monitoring will often allow the rider or experienced mechanic to determine whether their frame is still safe to ride, but with carbon the damage usually manifests inside the structure, in this case, frame tubing. This makes it difficult to assess damage without the use of very specific and, generally, rare diagnostic tools. Thus, I think of titanium as the highest performing material when it comes to considering all the relevant aspects:

  • Corrosion resistance – titanium doesn’t rust, but it can sustain galvanic corrosion, pitting and crevice corrosion if contact interfaces are not properly treated. This is easy to accomplish with copper paste.

  • Strength and Fatigue life – titanium and steel are strong and retain their strength for a long time; titanium is the stronger of the two

  • Dent resistance – when compared to comparable frames in other materials, titanium is the most dent resistant (or crack resistant in the case of carbon)

  • Ride quality – with tubing shaping and configuration, titanium can provide whatever ride quality one wants, with the exception of cases where aero tubes are required. Only carbon does that combo well

  • Structural integrity monitoring – titanium is easy to monitor for cracking, as it can seen by the eye well before a critical failure is likely to occur. The same is not true for aluminum, which will fail catastrophically very quickly once a crack forms. Steel’s failure progression is in between titanium and aluminum, and can often be spotted before total failure. Carbon can be difficult to detect before total failure.

These are the reasons I think of titanium as the material that provides the highest degree of confidence and certainty when it comes to structural integrity.

This matters a lot to me whenever I crash a bike and want to be able to determine via visual inspection whether it’s ok. The same applies to my components. When I’m travelling, and my bike is thrown into and out of planes, I want to be able to inspect it and determine whether it was damaged. I believe titanium offers the best attributes in these cases, albeit at a cost.

When performance at an excellent price is the priority, aluminum offers the best value, but aluminum frames simply don’t last for ages. The nature of the material makes it a great performer for a handful of years, but after that, unless you have access to very effective diagnostic tools, you’ll need to retire the frame (or component) before it fails (again, because the duration between beginning of failure phase and end is short).

So, while titanium is notoriously difficult to work with on the production end of the equation, which contributes to its relatively high cost, it is very well positioned as a material to focus on when investing in a frame that is meant to serve years of riding. For this reason riders often put a tonne of thought and care into their choice of titanium build – the majority of which are custom or semi-custom – and end up developing strong attachments to their ti bikes. This is why I tend to think of titanium as the material that makes sense for riders to focus on once they have a clear sense of what they want from the bike, and have the confidence to commit to that vision. I’m working with T-Lab Bikes, based in Montreal, Quebec, on developing their gravel platform to meet the needs of the whole spectrum of gravel riding, deploying a range of geometry formats and configurations. I’ve been really impressed by their engineering and manufacturing skills, and the quality of their builds.

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(UPDATE) I’ve had the pleasure of spending a bunch of time on my new T-Lab X3 titanium gravel bike (above) since September, 2019. The bike is absolutely unique in ride quality, and easily my most comfortable frame over rough terrain; I love it! I’ve ridden all sorts of terrain on it, even raced it cyclocross, and it has become my favourite bike. More to come on this one soon!

If you need wheels for whatever bike you land on, I encourage you to check out the local brand I help out with, good friends of mine: Woven Precision Handbuilts. I run the wheels through the paces and have total confidence them, and the 700c and 650b options are on the money. All Woven wheels are hand built in Ottawa (once in a while by me), and come at an excellent price.

Sorry that was misleading, I’m not carrying camping gear on the bike, just taking it with me camping. But steel was my first choice. And It makes total sense to budget for good wheels. Thanks I’ll definitely follow up on that. I didn’t know where to get hand built in Canada.

Thanks again….you’re amazing. I passed your email on to my equally bike passionate buddy who is also looking for a gravel bike.

Super, your life is all the simpler without having to figure out fitting gear to your bike! If you want the most stable platform, something like the Brodie Elan Vital will deliver the goods. 

I hope you guys land on bikes that make you want to ride and love doing so!

If you have questions you think I can help with, submit them to teknecycling@gmail.com

Matt Surch

Father of two, Matt has been blogging since 2007, melding his passion for all things cycling and philosophy, specifically with regard to the philosophy of technology, ethics, and cognitive science.

https://www.teknecycling.com
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MATTER OF FACT: Increasing Stability on Gravel