International Dealer News IDN 149 June/July 2019 | Page 30
PRO GuIDe eXTRa
Supersprox unveils new
generation sprockets
for KTM/Husqvarna
Factory racing teams around the world are
always looking for an edge. Supersprox has
worked with many top teams over the past
60 years with constant development as new
materials and manufacturing techniques
become available and in response to the
feedback they get from the race team
managers they work with.
Supersprox General Manager DJ Maughfling says:
"In the past three years, engine performance has
affected the durability of the commonly used
technologies for the production of engine drive
sprockets. The engineers here at Supersprox are
responding with a different approach.
"We have looked closely at all the products in our
racing line, because in the near future historically
suitable technologies will start to age out. Bikes are
getting too powerful and racing partners are pushing
to have their suppliers think outside the box.
"With assistance from a technical institute, we have
approached this problem scientifically and been able
to analyse how weak points in the parts produced
using established manufacturing techniques develop
under the varying conditions and loads they are
exposed to. The results were surprising. We realised
'closed die,
hot forging'
it would not be possible to solve the issues with
existing metallurgy. A solution was proposed on the
bases of a radical change in process.
"So now we are embarking on a new technique -
closed die, hot forging."
Supersprox claims that this new process increases
the sprocket tooth and core strength by more than
20%. Compared to billet machined parts, the process
offers significant advantages. In a part made from
billet, flow lines develop in the microstructure. The
properties become anisotropic - that is to say that
the physical properties of the material have a
different value when loaded equally in different
directions, meaning parts can fail under dynamic
stress.
"During forging, impurities align themselves along
these flow lines. The microstructure flow lines in a
forged part will be much finer than a billet
microstructure and therefore stronger and more
durable. Special details are being added into the
forging to provide the highest strength at the teeth
and spline area - something that can't be done with
CNC-machining a billet".
DJ says that a unique ultra-low carbon steel
(purchased in Japan) has been used for the sprockets,
helping to provide a very stable condition in the base
metal. Although the sprocket doesn't have holes
'microstructure
flow lines'
drilled, DJ says it is actually lighter than the OEM
sprocket because of the surface indentations.
The aluminium core in this sprocket is a technical
feature, allowing the sprocket to retain a critical
thickness in an area where steel is not required.
Currently available for KTM and Husqvarna models,
DJ says "we will test market reaction and
understanding, listen to feedback, and if the
performance and response to these new sprockets is
as positive as we expect it to be, then we will start
to expand use of the new techniques elsewhere in
our range."
Supersprox are well known as the inventors of the
patented hybrid sprocket, combining steel teeth with
an aluminium core. In 2018/2019, Supersprox
gained further five additional world titles, including
the World Endurance Cup and the Dakar Rally, both
using the original design of the Supersprox-stealth
sprocket.
Supersprox says it is one of the
first sprocket manufacturers to
use closed die, hot forging
Forged blank
Billet blank
Forged blank, showing a finer grain structure when compared to a billet machined part.
30
INTERNATIONAL DEALER NEWS - JUNE/JULY 2019
SUPERSPROX
Czech Republic,
Poland, Ukraine
[email protected]
www.supersprox.com
www.idnmag.com