It's
no secret Easton makes some of the most sophisticated tubing on
the market. When Niner Bikes was trying to decide what frame material
to work with for their first frame, Easton GX2 Scandium stuck out
as the clear choice for both weight consciousness and ride quality.
Scandium
is a rare earth element and an additive used as a grain refiner
in alloys. It's biggest purpose is to minimize the heat effected
zone of a welded tube. Every time two tubes are welded together,
there is a heat effected zone that weakens the overall strength
of the tubing. This heat effected zone, on a standard 7000 series
aluminum frame, can be as long as several inches. Any internal
butting of the tubing should, for maximum strength, take place
after the heat effected zone. On Easton's GX2 Scandium tubeset,
this heat effected zone is reduced to almost nothing, giving Easton
the ability to make tubing that butts significantly closer to
the weld, without compromising strength.
Scandium,
however, does not increase the yield strength of an alloy. This
is a critical component to the equation. Simply adding Scandium
to a 7000 series tube, as some other companies are doing, does
not increase the strength of the frame. This results in requiring
nearly the same exact tube profiles as a standard 7000 series
frame which results in a ride quality as harsh as a standard 7000
series frame, thus negating the benefits of the Scandium additive.
Easton developed a proprietary alloy with a substantially increased
yield strength than that of a standard 7000 series alloy. This
gave Easton the ability to use smaller diameter tubing and thinner
walls to result in a more compliant ride while not sacrificing
the fatigue strength of the frame.
It's important to note that while the external diameters of the
tubing plays a role in the bikes ride quality, internal wall thickness
of these tubes plays an equally important role. Balancing the
two is an art form in ride quality, especially with the increased
demands that a single speed rider puts on the frame. Mashing on
the pedals in extreme uphill situations with no ability to shift
requires an extremely stiff bottom bracket area and front triangle.
Niner's goal with the One 9 was to balance weight, compliancy,
and stiffness in the perfect balance. Easton was able to supply
the custom tubing to make it happen.