Road bike frames have come a long way. But are they what they are made out to be in cycling media and by bike manufacturers? Let’s find out.
Having covered road bike selection in an earlier post, this focuses on bike frame materials which can be quite complex. Each material interestingly has it’s own personality as well as a purpose that a particular rider appreciates and wants.
Frames
The 4 common materials for road bike frames and even for other bikes types are;
- Steel (alloy) – oldest and easily recognisable in view of their thin frame tubes. It is dense and strong, and therefore frame tubes can be thin. It’s drawbacks are it’s weight and it is hard to manufacture in scale. Popular with those who like a long lasting custom made frame. Also popular with Uni students in the second hand market as the bikes can last and can be resold. Plus a retro fashion statement.
- Aluminium (alloy)- most popular as it affordable and great for entry and mid level bike enthusiasts or just for general commuting. Triple butted frame technology has introduced some performance quality frames but they come with a higher price tag.
- Carbon fibre – lightest material, choice of pro riders as well as serious amateurs. It is however labour intensive to manufacture and therefore costly with the exception of titanium frames.
- Titanium – expensive as it is a hard material to work with and to manufacture in scale. Lighter than steel and famed for its shelf life and near zero maintenance. It is tough and can handle knocks. Hence used in submarines and aircraft. But heavier than carbon.
Frame geometry
Before going into frame material characteristics, a reminder to pick bike geometry first. I have covered this on my post on road bike selection.
Bike manufacturers display frame geometry as a matter of course on their website. These measurements are similar or near identical across brands with slight variations. Geometry is material agnostic and relates to the rider’s posture to achieve comfort, reduce drag and to maximise transfer of power to the pedals. Goes hand in hand with a proper bike-fit.
Weight and motion
Firstly a frame is not a moving part and has no moving parts. It is a static physical structure that has one very significant impact in regard to motion and that is weight.
Weight is the single biggest reason why carbon fibre frames are immensely popular among professional and serious amateur cyclists. It is lighter and far better to climb hills and for speed.
Aerodynamics
Aerodynamics or the term “aero” are probably the most abused area in bike marketing when applied to road bike frames. These terms including “wind tunnel” and “drag” are often used in marketing collateral and in cycling media reviews.
There are far more important areas for road bike when it comes to aerodynamics than the frame. They are the cyclist, the wheels and the helmet. The frame is secondary with focus on fork, headset and seat post being more aerodynamic.
If you are on the heavy side, dropping your weight and reducing your profile will do much more. Getting your posture right goes a long way in aerodynamics. Invest in better or carbon wheels and helmet rather than the frame if you are looking to reduce drag and are into speed.
Stiffness
Lateral stiffness is important in bike frames. Pedal stokes need to be efficiently transmitted without the frame absorbing some of it or flexing too much. Carbon can be shaped more easily for lateral stiffness compared to other materials without adding much weight. After weight, stiffness in the right area is second most important attribute. Carbon handles this best allowing for the frame to be targeted for stiffness and where it needs to flex.
Vertical stiffness however is a negative as it leads to harsh rides. Aluminium suffers from this as the vertical down tube is bigger as aluminium cannot handle flex as it leads to metal fatigue. This is where steel and titanium do better as they can flex and not suffer from fatigue compared to aluminium.
Ride comfort
Road bike frames do have an impact on ride comfort but not to the extent that marketing makes it out to be. Take it with a pinch of salt.
Steel is dense and therefore has slimmer tubes. Slimmer steel tubes allow flex and together with titanium has a damping effect. Next to follow is carbon. Aluminium however is relatively harsh in comparison. Carbon forks are therefore used in better quality aluminium bikes for damping the harshness. The ride comfort however is more influenced by other attributes than the frame which I will cover under Ride Comfort part 2 below.
The area of focus in the frame for ride comfort is the down tube and seat post of the frame, the area on which the rider sits on. All other materials are more or less the same. Most high end brands focus on the seat tube post technology to provide the flex and not on the frame itself.
Ride comfort part 2
But here is a revelation if your intuition has not stepped in. Wheels and tyres have far more influence on ride comfort than any frame. Broader tyres and lower PSI inflation allows for better ride comfort. In recent years, road bike tyre width that previously hovered around size 23 and 25 for years has now found favour in size 28. Newer frames are now accepting width of 30 and 32.
Second most important factor when it comes to ride comfort is the saddle. Read up on sit bones and work out the type of saddle that you want. Take note of saddle cut-offs which allows reduction in tissue pressure when seated. Online forums are helpful with forum members providing their view on various saddles they have tired.
Cycling media reviews cover ride comfort as a matter of course when it comes to road bike frames. Narratives alluding to frame as primary factor for ride comfort is not based on science. The more responsible ones now use the term “feel” which is subjective.
One of my bikes is a titanium and it is my favourite bike. Despite claims such as buttery smooth ride etc it is really up to my imagination though better than my aluminium bikes. But I do get compliments on my way up the Norton.
More on material types
Steel requires maintenance to avoid rust. Any damage though is relatively easier to fix. Look after it and it can go the distance. Unfortunately it is too heavy for most people. It is however the best material for touring and long distance travel bikes. A true and reliable workhorse.
Aluminium is cost effective but has a relatively shorter shelf life because it is prone to metal fatigue. No amount of maintenance will stop metal fatigue if used regularly and ridden hard. It’s the nature of the material. Just need to inspect the joints in later years. It is however the best bike material for your errands, commuting and easy rides as it is cost effective.
More on carbon care
Carbon does not need much maintenance but careful handling and regular inspection at pressure points are a must. It has the least impact resistance of the 4 materials. It is common practice not to lend your carbon bike to anyone. You might not be aware if they are dropped it or had a knock. No issues with bikes of other materials as they can take a lot.
Do note that you have to be careful about buying a second hand carbon bike. Thought it has excellent shelf life, the material is brittle. Cracks and even a fracture (delamination for this material would be more appropriate) may not be visible to the eye and may be dangerous to ride. Identification of flaws require expensive equipment such as ultrasound scanning and repairs are costly.
Trade-offs
The weight trade-off for carbon bike however is well worth it. One just have to be careful with carbon bike handling compared to all other materials.
Titanium is one that some will eventually have in their stable as it lasts a lifetime. No paint work necessary, does not rust and tough as nails. Suitable if you travel a lot and don’t have cumbersome hard cases to protect your bike from overzealous baggage handlers.
Using the same frame, you can upgrade to the latest groupset to keep up with the times and it still will look great.
Careful of hyped marketing
In the last 20 years marketing has overtaken engineering in some respects. Unjustifiable claims, irrelevant test data and prices that don’t stack up are some concerns. And these are particularly targeted at the high end road bike market.
There are however some fantastic companies with a proven record for excellent engineering. Time (French) Pinarello (Italian), Colnago (Italian) Bianchi (Italian, Giant (Taiwanese), Wilier (Italian) and BMC (Swiss) come to mind. Associated with innovation, quality, value, history and lack of misleading claims. They are also not fraught with design faults or overhyped marketing.
Cycling media
Trade and cycling media are typically not candid with their reviews. Their livelihood depends on brands sending them samples for reviews, buying advertisement spaces and sponsoring events. Any boycott would be serious to their business. It was the same in the car industry until consumer bodies started sponsoring surveys and reviews.
I do remember a high end bike company that was famous for its creaky bottom bracket for years. They even had their bikes in the Grand Tours and the Tour de France. The positive reviews and sales however continued.
Cycling media however are great in other respects. With tips on installing and servicing of parts, bike care, new bike trends and cycling tips etc. GCN is probably the best at it.
Internet and rise of independent experts
The internet is now the medium of choice for discerning consumers. They can read about bikes and check on known faulty designs, poor manufacturing controls, poor service and unjustified pushback on warranty claims.
Even more fortunate is the rise of engineers who are not part of the cycling industry. They have become custodians of sort for the cycling public. With the security of a day job and being serious bike enthusiasts they are not dependent on the cycling trade.
They have called out long standing and new faulty designs and misleading marketing. Have even led to product recalls and forced brands to reverse decisions on rejected warranty claims. They do it by YouTube show and tell. So do a search here as well.
Some recommendations
Still confused, too many things to consider? Well here are some recommendations for a road bike frame to help you.
- Get a carbon fibre frame that comes from a reliable brand if you are serious about cycling for fitness or competition. Mid range frames will do. You will be in the company of many and you would be in the Norton Summit train on weekends eventually.
- Get an aluminium bike that is double or triple butted if you want to use a bike for all purposes. You can still make it to Norton Summit. Value for money.
- Good groupsets and wheels make a lot of difference in terms of comfort and pedalling efficiency. So invest at a minimum in the entry level “performance range”. I have covered this in an earlier post about road bike selection.
- If you are struggling with brands, Giant is a safe bet. Certainly not a compromise even for top end competition. It has a store in the middle of Adelaide CBD. Manufacturer’s physical store presence makes a lot of difference especially when dealing with warranty claims.
Bike frame carbon fibre pioneers
Giant pioneered carbon fibre bike technology and are experts on it bar none with the exceptions of Look and Time of France. They are the biggest consumer of raw carbon fibres in the World as they do contract manufacturing on an extensive scale. They do it for well known and expensive brands around the World as well as for their own brand. Confidentiality clauses bind them from disclosing what other brands they manufacture for but it is common knowledge.
Pro riders use Giant and bikes contract manufactured by Giant. You see them in Grand Tours and the Tour de France. They are not known for hype marketing, irrelevant R&D data or faulty designs. They have physical stores in all major cities of the World.
Lastly if you are keen on a particular brand, goggle the brand. There are lots of great brands out there, just spend some time going thru the various forums. As you do your search, use the following terms- “faulty design” and “warranty claims” with the brand name. It will prove helpful.
Hopefully this post on road bike frames provides a better of understanding of frame materials and their particular characteristics.