User Guide

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LEMOND STEEL
Steel is real
Steel is the traditional material of choice
for bikes, dating back to the early years of
bicycling. The advantages of steel are many.
Traditional steels are inexpensive to make,
and inexpensive for the frame builder to
work with. Steel can be welded or brazed,
both easy techniques (for a skilled crafts-
man) that allow a creative joining of mate-
rial. In other words, steel allows a freedom
of design, at an affordable cost. Last, steel
has excellent strength, stiffness, and fatigue
resistance, all important factors when mak-
ing a lightweight efficient structure like a
bicycle frame. These factors should explain
why steel has been the traditional choice for
frame building for the last century.
It’s got the feel
Over the last century, a huge number of
steel bikes have been built. The early ones
were ordinarys, or highwheelers. Some were
fancy adult tricycles. Some were heavy
paperboy specials. And some were exotic,
super light racers.
The point here is that a lot of experi-
mentation has been done with steel bike
frames. Through science, or trial-and-error,
steel bikes have been made of all sorts of
shapes, sizes, tube diameters, and wall thick-
nesses. Because of the design and construc-
tion freedom of steel, lots of people have
had the opportunity to experiment. Over the
years, the parameters of steel bikes have
become well defined. We know how light they
can be made, and how to make them ride
well.
Through the years, enough steel bikes
have failed for us to understand what steel
can and cannot be made to do. And enough
designs have been ride-tested to know what
rides well and what doesn’t. Basically, the
experience gained over the least 100 years
makes the best steel bike a refined, quality
machine that’s as light as it can be and offers
the best possible ride.
Not all steel is the same
Steel has a high modulus. In other words,
it’s pretty stiff. And that’s true of all steel.
There’s hardly any difference in the stiffness
of a high-end steel like Reynold’s 853, and
the ‘tensile’ steel found on a child’s bike.
Likewise, ‘tensile’ steel and Reynolds 853
have the same density, or weight per unit
volume. In other words, a cubic inch of
Reynolds 853 is not any lighter than a cubic
inch of tensile steel.
There is, however, a large difference in
the tensile strength of the various steel
alloys. This difference requires that to be
equally durable, more low strength material
is required to build a structure than would
be needed of a high-strength material. This
need for more material somewhat explains
how a frame built from Reynolds 853 can be
so much lighter than a tensile steel frame.
Mechanical properties vs. Finished goods
As we said earlier, steel can be joined in a
number of ways. It can be bonded, riveted,
welded, brazed, and more. Of these, the most
popular in bike construction today is TIG
welding. Welding involves heating the materi-
als until molten, and letting them cool into
a single, solid piece. Sometimes additional
material is added in the form of a welding
rod.
As steel is brought to these high tempera-
tures and cooled, the molecules in the steel
undergo changes. Depending on the temper-
atures, and the length of time at a given
temperature, the molecules will reform into
microscopic crystals of varying structures.
There is a wide variety of crystalline struc-
tures possible, with an equally varied assort-
ment of mechanical properties of the welded
state. To simplify, we can say that welding
changes the steel, and it’s common for the
steel to lose strength as a result of welding.
In bike frame design, a good engineer will
compensate for the expected strength loss of
welding. They will design the tubing to be a
little thicker at the heat affected zone (HAZ)
so that the end result, the finished structure,
provides the required strength.
Steel technology leader
The Reynolds company of Great Britain
(not the American company that makes alu-
minum foil) has been a leader in steel bicycle
tubing since they developed the butting pro-
cess in 1898.
Since 1930, racing cyclists all over
the world have ridden frames built from
Reynolds 531. This proprietary manganese-
molybdenum steel alloy offered a blend of
strength and ease of manufacture that was
ideal for lugged and brazed construction.