THE
HEART AND SOUL OF BICYCLE FRAME MATERIALS
Written by Mike Palmeri, owner of Cartecay Bike Shop in Ellijay, GA. Mike was certified in 1983 by the Schwinn Bicycle School in Chicago, Illinois and re-certified in 2000 by the United Bicycle Institute in Ashland, Oregon. He is a certified bicycle mechanic, suspension specialist, a DT Swiss master wheel builder, and has been in the bike business since 1979.
Steel,
aluminum, titanium, and carbon fiber are all common bicycle frame materials
that bike manufacturers use today. The
characteristics of each material: weight, appearance, function, benefits and
limitations, can lead or mislead the consumer when deciding which bicycle to
purchase.
Bicycle
manufacturers try to meet new trends in the industry by sparking consumer
interest and offering new and exciting space-age frame materials. Often times, the substance behind claims of
super strength, resilience and lightweight is little more than marketing
fare. The far majority of bicycle frame
construction today is from steel and aluminum.
STEEL! Man, steel is HEAVY! That’s the comment I hear almost every day
from new bicycle consumers. Steel is
an exceptionally versatile material, and can exhibit a wide range of physical
and mechanical properties. When steel
is formed into bicycle tubing, it can be light, strong and comparatively
inexpensive. To address the heavy steel
comments, high tensile steel is commonly used in department store bicycle
frames. STAY AWAY….stay FAR, FAR away!
Lightweight steel incorporates different percentages of alloying
elements that improve the weight, strength, and overall performance of the
metal. So, if steel is such a great
frame material, why is the selection of steel bicycle frames available to the
consumer decreasing? Because, steel
takes more manpower to produce and many of the larger manufacturers are scaling
back their steel frame production.
Steel provides a softer ride, and can be as light or lighter than
aluminum. Steel is great for hardtail
mountain bikes and road bike frames. I
highly recommend steel hardtails for cross-county racers, adventure racers,
long rides on gravel, and any rides 3-6 hours long. As I mentioned, many manufacturers are building aluminum frames,
but steel frames are still out there.
It is worth the time to research the smaller frame builders who
specialize in steel production.
So
why are there so many aluminum frame bicycles?
Aluminum tubing has applications that are popular today. They are lightweight and have low production
cost. The manufacturer can build ten
aluminum frames for every one steel frame.
More frames equal more sales. The
most common aluminum used is the 6000 and 7000 series, and aluminum can be
welded or bonded. Aluminum is a much
stiffer metal than steel, but has only one third the fatigue strength, which is
the ability to withstand many cycles of stress. Aluminum is not necessarily inferior as these properties have
their place in the bicycle industry.
Aluminum frames deliver a harsher, stiffer ride. Many riders complain of the lack of shock
absorption, resulting in the cyclist’s premature fatigue. But, aluminum can be a great frame material
for dual suspension bikes or for larger riders.
Titanium. Thanks to the aerospace industry and the
military, titanium tubing for bicycle frames is here to stay. I love titanium tubing. It has an excellent strength to weight
ratio, it is fatigue and corrosion resistant, and very resilient. Titanium is the preferred frame material for
more than a few cyclists. The major
drawback: titanium bicycle frames made in the USA are not inexpensive. The high cost of titanium tubing is due to
the extensive labor involved in processing, and the highly skilled labor needed
to weld the frames into works of art.
Titanium is an ideal frame material for super light cross-country
mountain bike frames, dual suspension mountain bike frames, as well as road
bike frames.
Carbon
fiber. Give credit to Thomas Edison for
the first purposeful creation of carbon fibers. In 1878, he converted cotton fibers into carbon in his search for
lamp filament material. In the past 20
years, carbon fiber has come to be used extensively in many sports
applications. Carbon fiber is a
composite material, which means it contains a reinforcement in the form of
fibers or particles. Bicycle frames can
use carbon fiber exclusively, or in combination with aluminum, steel or
titanium. Some full carbon frames are
made in a mold and are essentially one piece.
Carbon fiber is also used to wrap over aluminum parts to make small
components like cranks, brake levers, and the rear ends of steel, aluminum or
titanium road frames. Carbon fiber
frames have a short life span, but are great for long road riding (biathalons,
triathalons). Carbon is not recommended
for off-road bicycle frames.
Those are the basics of bicycle frame materials. If you have any questions, or need more specifics, call (706-635-2453) or Send mail to Cartecay Bikes