The first bicycles in the early 1800s were made from wood. By the late 19th century,
steel was widely used. Since then, advancements
in technology have brought aluminium, titanium and carbon fibre to the bike industry. Developments
have not stopped there with a recent resurgence in the use of steel tubing.
The biggest change in terms of technology and manufacturing over the last 50 years has
been in materials and those influences very often come from other industries such as the
motorsport industry, aviation industry. These are all areas which will use high end materials
and also manufacturing processes such as the use of carbon fibre, the use of alloys.
Steel was historically the material of choice in bicycle manufacturing due to its particular
properties, with British company Reynolds being at the forefront of steel tubing design
and production.
We tend to use steel on our lower end bikes because it’s affordable, it’s easy to
build with and it still makes a great product.
Steel frames offer us a lot of benefits in that we’re using cutting edge Reynolds 953
tubing, which is super light. A great benefit with
steel is the safety factor in that steel doesn’t just fail
catastrophically.
You've got a very durable material, one that can be recycled, one that certainly as far
as we can see, a rider theoretically could still
be riding that bike 20, 30 or 40 years from now and still
find the ride quality good.
When it comes to more performance orientated products, aluminium starts to come into the
field. Again it’s relatively affordable, so we can build good, lightweight bikes at
good prices. It is also a material that with the new hydra
forming techniques that you can build some really
complex shapes.
Aluminium offered the opportunity to use much bigger tube sets for increased stiffness,
also created quite a new look for bikes.
Aluminium is one of the greatest materials to building bicycles out of, it's cheap, it's
light, it's strong and if you use it properly you can
build an absolutely fantastic bike.
We do work in aluminium especially alloys known as 6061 and 7005 but for Reynolds they
don't have the very high strength to weight ratio we would use for the higher end frames
that tubing that we produce for our customers.
Titanium is used in the aerospace, military and automotive industries to produce lightweight
alloys. This low density and high strength material, comparable to steel on a stiffness
to weight ratio, was introduced to the industry
to build light, strong bikes with a good fatigue life.
Titanium is a really great material, really super light but also a little bit flexy so
you don't get the stiffness but you get really good weight
and also good durability out of it.
Titanium is one of those wonder materials that has a great ride quality to it, so does
steel, but a titanium bike would be probably twice as
expensive, if not three times as expensive and
only marginally lighter, so what are the benefits to that rider in building that bike out of
titanium if they can't afford it?
The techniques for welding titanium are, have to be actually very precise because you can
actually, if you don't know what you're doing with a titanium frame, you can actually have
a very poor weld so there are very few people
who make very good titanium frames but the cost
of the material can be very, very high.
Then came carbon fibre which pretty much revolutionised the whole road bike industry
because that allows designers to achieve shapes and weights that was never possible with
aluminium or any other material before that.
In 85 with the Tapie Group we started working with carbon and that’s where we really started
to evolve. We researched every are to be able to have the lightest
possible with the highest level of performance.
Carbon fibre is in many ways the ultimate material for a performance machine. There
are very few materials around at the moment which combine
the same levels of strength, lightweight and versatility in terms of manufacturing.
You know if it’s good enough for a Formula 1 car
then it’s good enough for a bicycle as well.
The best today above all is carbon. Because carbon is a constant material. It’s tissue
with resin and once you’ve shaped it, it stays in shape.
Carbon because of the flexibility it gives you tube shapes means its ideal, ideal for
exploring aero designs.
The downside of carbon fibre is that it’s an expensive process. It’s an expensive
process, an expensive material to work with because it’s
fairly labour intensive.
You feel every bump in the road on a carbon fibre bike. The steel frame is a little bit
more forgiving.
In light of the disadvantages of working with carbon fibre, steel has seen a recent resurgence
in bicycle manufacturing even at a high performance level.
It’s very encouraging to see steel back in the pro peloton. The UCI weight limit 6.8
kilos for a bike can easily be achieved with a steel bike
with standard components that are around now, so the weight per say is not an issue.
In recent years we’ve seen and series of dubbed super steels arrive on the scene which
offer, offer an incredible tensile strength, which
means we’re able to draw the tube wall diameters very thin, so achieve weights that were previously
unachievable.
What we are seeing from the likes of Reynolds and other quality tubing manufacturers is
some great lightweight, quality tube sets coming along. So you're seeing an increasing
number of performance bikes with steel in them.
Over the years the strength of metals have changed dramatically. Even the Reynolds 531
invented in 1935, the tensile strength of cold worked 531 was up at 750 to 800 megapascals
back then. Our Reynolds 853 is up at the 1200 megapascals and we've been doing that tube
for about 15-20 years now and when we move onto the Reynolds 953 we're looking at
between 1800 and 2000 megapascals
Material choice is a whole balance of different scenarios into what we use the material, what
price point and what bike. Price of material is probably the principle one, but then it's
also what is the ride quality we want at the end of it.
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