The Tech Forum

In this month’s Tech Forum, Eric Sakalowsky of Velo Europa Imports offers some important insight into the basics of different bicycle frame materials, and how you can select the right frame material to maximize your performance, comfort, and budget.

WHAT FRAME MATERIAL WILL WORK BEST FOR ME?

Different frame materials will dramatically impact how a bike rides, and by extension, how much you will ultimately ride your bike. In selecting the right frame, there are many issues to consider.

Let’s sidestep the various marketing claims typically thrown around by bicycle companies about frame materials, and make a no-nonsense inquiry into what to look for and why in terms of frame materials.

Here are some general guidelines concerning the frame selection process:

Go into the frame selection process with an open mind about particular frame materials, choosing instead to focus on what will work best for your levels of comfort and performance, and your overall budget.

There are two terms you will often hear in relation to frame choice—stiffness and ride quality. “Stiffness” refers to the rigidity of the bike, most often with focus on the bottom bracket area, where the rider’s energy is most directly applied to the bike.

The general thought is that a stiffer bottom bracket is better for power transfer; but, that can be dangerous for those who aren’t strong enough to use the stiff bike. Additionally, a rider’s strength decreases during a longer ride so it’s important to find the proper stiffness for you even as you fatigue. A bike that is too stiff can work as a detriment as it can actually sap energy and lead to potential injury (consider golf clubs that are too stiff or a tightly strung tennis racket and you’ll get a sense of what an overabundance of stiffness can cause).

“Ride quality” refers to how the bike feels as you ride over various road surfaces and terrain. An ideal bike is going to soak up the rougher patches of tarmac while still providing a good connection with the road.

Even the best frame material, when poorly fabricated, will not perform well, or feel right underneath you. Some manufacturers often attempt a “bait and switch”—they will hang really sharp components on a bike frame in an effort to create a compelling product while scrimping on the underlying frame material or build quality.

In selecting a frame, however, you will be better served by placing a premium on good frame craftsmanship—such as solid bonds or welds—from a reputable manufacturer over sleek-looking components that might be thrown on a lower-level frame in order to dress it up a bit.

Remember—the frame is the heart of the bike. Consequently, you should funnel the lion’s share of your bike budget towards an investment in a solid frame. A solid investment in a good frame is likely going to deliver you the biggest return in terms of comfort, performance, durability, and enjoyment. Plus, you can always improve on a good frame later by upgrading the components if or when your financial circumstances improve.

Moving on to consideration of different frame materials, here is some basic 411 regarding the most common frame materials:

Aluminum

Aluminum is a generic term that covers a very wide range of aluminum-based alloys. This material has an often-misplaced reputation for being stiff and uncomfortable.

Historically, cyclists liked the comparatively low weight, stiffness, and sharp handling of aluminum frames. However, the teeth-chattering ride of aluminum was often considered a major turn-off, and that lower ride quality caused many everyday cyclists to eschew aluminum frames.

Early aluminum frames could be justifiably criticized for delivering a rough ride. Vast improvements in aluminum fabrication, however, have produced more malleable and well-engineered alloys that offer cyclists a much improved ride quality.

When coupled with carbon rear-ends (chain stays and/or seat stays) and carbon front forks, most new aluminum frames deliver a cyclist a surprising combination of comfort and high-end performance. Equally important, aluminum alloy frames provide great value because the frame material is relatively inexpensive and doesn’t require the same production investment to fabricate. Choosing aluminum--instead of more expensive options like titanium or carbon—therefore offers you the prospect of a cost savings that you can direct toward higher-end wheels, drive train, etc., ultimately permitting you to cobble together a very solid complete bike geared toward a higher performance

Steel

“Steel is real. Real heavy.”

A classic phrase historically offered up by the cycling cognoscenti to describe steel. Steel is, after all, often considered a “vintage” material. New steel alloys, however, continue to be developed, fabricated, and shaped into bicycle frames.

Although today’s steel frames are not generally as light as their aluminum, carbon, or titanium counterparts, it is a sought-after frame material. Why? It’s simple—steel frames deliver a great ride quality, durability, and a classic look. Also, even though carbon or aluminum frames on the market today might be stiffer than steel, steel may be better choice for many cyclists because much of what is currently on the market is overbuilt for the average cyclist (refer to the comments on stiffness above).

An “overbuilt” frame is engineered beyond the needs of the average cyclist, creating a frame that is generally too stiff. The stiffness becomes and issue because the enthusiast cyclist (even very fit ones) do not have the necessary strength to properly solicit the frame.

A frame should move beneath the rider in a predictable fashion and help foster something of a metronome effect to heighten the bike’s dynamics, help the rider’s pedal stroke, and ensure injury prevention. So, as the rider pushes on the pedals, the frame should actually move and “load” something like the way a spring would when compressed. As the pedal stroke continues and the “un-loaded” frame snaps back as the cycle continues, this helps with the dynamics noted above.

If the frame is too stiff then the rider cannot “load” the frame. There is a detrimental effect to the energy transfer and bike’s dynamics as well as the increased chance of injury. As the rider applies force to the pedals there is, ideally, a transfer of the energy into the drive train of the bike and the bike frame all of which allows the bike to move forward. With a bike that is too stiff for the rider such that the rider cannot “load” the frame, some of this energy comes back into the rider’s body itself, placing significant stress and strain on the rider’s joints and ligaments. This can lead to something like a rider’s version of “tennis elbow,” as the strain is from a similar cause. You need to find the right blend of stiffness for you, the individual rider.

Conversely, a frame that doesn’t snap back at all (something that we could consider as “sloppy” in the bottom bracket) won’t load and snap back at all which kills the metronome effect and can be an energy sapper too.

Steel is also the material of choice for a myriad of custom frame builders, so if you need something made-to-measure, steel might be the order for you. If you are looking for a more performance oriented ride, consider a steel frame with a carbon rear-end and full-carbon fork. This combination will give you the smooth ride historically offered up by steel along with a stiff rear end that delivers efficient power transfer and acceleration.

Lastly, steel frames like their aluminum counterparts, typically cost less than carbon or titanium frames. Steel therefore offers a great ride value.

Titanium

Once considered the crown jewel of frame materials, titanium has lost some of its luster (bad pun intended) as more and more carbon frames have hit the market.

Over the past few years, however, titanium has made strides to advance well beyond earlier generations to offer light, dynamic riding options. Well-made titanium bikes do carry a substantial price tag because of the high raw material costs and production skill required for the manufacture of the frames. Titanium frames therefore are not the frame choice for the budget-minded.

Typically, titanium frames are produced with rounded tubes. Titanium is a relatively flexible metal and that suppleness doesn’t necessarily work well for a bicycle frame where you want the entire bike to track along the same line to ensure solid handling and safety. Titanium’s flexibility does offer a cyclist a plush ride. But, those cyclists—namely racers—looking for a stiff, performance-oriented ride typically complain that titanium frames deliver a ride that is bit too “loose,” and that ride quality negatively impacts overall bike handling. To date, round-tubed titanium frames haven’t really addressed this shortcoming.

But, given titanium’s unique ride properties, titanium frames offer a great choice those cyclists who are less concerned with a race-ready, high performance rides, and instead are more focused on getting a plush, “couch-like” ride. Titanium therefore is a great frame choice for older cyclists, or century riders.

Carbon

Carbon is firmly ensconced as today’s frame material of choice. These frames typically boast a low weight, stiffness, and tight handling properties on par with their aluminum counterparts and, equally significant, a more forgiving ride. Given those qualities, racers and cyclists concerned with a high-performance oriented ride usually covet carbon frames.

Carbon frames, however, are not for everyone. Carbon comes in a wide array of build quality and performance grades. It’s easy to be seduced by the “carbon” moniker, but it’s best to weigh it against your budget and desired performance characteristics.

Lower-priced carbon frames are generally cheap for a reason—production quality isn’t there and these frames typically feature a lower grade of carbon fiber whose performance properties and longevity are questionable. The current state of the bicycle-building world is that many of the more widely available brands feature products made by subcontracted vendors whose Asian production helps to cut costs. Vendors can change, product quality can vary, and sometimes well-engineered frames are made with a sub-par grade of carbon that will have a significant impact on the frame’s quality.

Small frame builders and some of the more reputable big manufacturers with U.S. or Europe based operations can definitely be trusted to deliver you a fine carbon frame. If you are cyclist focused on a high-performance oriented ride, or you are one of those lucky few who have avoided a hit from our current economic downturn, you should definitely consider carbon given the fantastic combination of weight, stiffness, and ride quality it delivers.

When looking at different frames and frame materials, consider all of the above. Consider what qualities are most important to you: ride quality, weight, bike-handling, cost, or some kind of combination of the three. Ultimately, you need to come out of this selection process having invested in a bike frame that is going to work for you now and (hopefully) in the coming years. Remember—you can always upgrade components. You should therefore strive to get the best frame that your money can buy, while simultaneously trying to set aside enough for a fair amount of your remaining budget towards a good set of wheels too. Don’t be afraid to go to a dealer who can sell you a frameset and assemble the bike from various parts instead of settling for something off-the-rack. Just as you’d want to build your house on a strong foundation, a bike needs to start with a good frame.

About the author: Eric Sakalowsky is an accomplished USCF CAT 2 racer, and the Co-Owner of Cyfac International, builder of handcrafted bicycles based in France’s Loire Valley. Mr. Sakalowsky is a certified Cyfac Postural System fit specialist. He lives in Haverford, PA with his wife Elodie and young daughter Esmée. He can be reached at esakalowsky@veloeuropa.com.