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HUGE
STOCKS • FRIENDLY, EXPERT ADVICE • WORLDWIDE EXPORT
• HIGHEST QUALITY PARTS • SPEEDY DELIVERY
Frequently
asked questions
Here
are some frequently asked questions and
their answers from BlackStone Tek / BST |
1. What
performance gains can I expect by
upgrading to BST wheels?
2. How
does Carbon Fibre compare with Magnesium
and Aluminium alloys?
3. What
do BST wheels include?
4. How
much safer are Carbon Fibre wheels
than standard wheels?
5. What
are the physical properties of Prepreg
Carbon Fibre that make it particularly
suitable for wheels?
6. How
much stronger are BST Carbon Fibre
Wheels than conventional wheels?
7. Do
BST wheels have TUV certification?
8. How
much lighter are BST wheels than
standard wheels?
9. How
long have BST wheels been in development?
10. What
is the difference between wet lay-up
and the Prepreg construction, as
used in BST wheels?
11. How long
do Carbon Fibre wheels last?
12. How much
horsepower are BST rims rated for?
Q: What
performance gains can I expect by
upgrading to BST wheels?
A: UK sports bike magazine, SuperBike,
performed an independent two-day
test at Spain’s Almeria circuit
using a Honda FireBlade - which
already has as original equipment
particularly light wheels.
The bike was in a mild state of
tune, representing a typical modified
road/street/track day sports bike
by having; race exhaust, Dynojet
Power Commander, double-bubble screen,
Sprint steering damper, a two teeth
larger rear sprocket and upgraded
brake pads.
The rider was already familiar with
the circuit after having ridden
there twice before. The first day’s
testing took place with standard
wheels and the only change for the
second day was the substitution
of BST wheels. Weather conditions
were unchanged and the following
was observed:
- Acceleration was noticeably stronger
with the rider reporting “it
felt as though it had gained ten
horsepower”
- The bike could be braked later
- The bike could be turned more
easily
- Top speed at the end of the main
straight was increased by 5mph
- Lap times fell by a full 3 seconds
– although the rider did report
“pulling the pin out”
as he felt very confident on the
bike during the second day
These results are consistent with
performance gains normally found
by virtue of the combination of
reduced unsprung weight and reduced
rotational inertia provided by BST
wheels. Even if a bike is not being
used on a circuit, the same benefits
of increased performance and rideability
also apply to road/street use.
Q: How does
Carbon Fibre compare with Magnesium
and Aluminium alloys?
A: Wheels manufactured from metal
are either cast, forged, machined,
or manufactured as a combination
of the three processes. Aluminium
wheels have been around for many
years. They are relatively easy
to manufacture and also relatively
cheap, but they are heavy because
of the density to strength ratio
of Aluminium (how much strength
you get per kilogram of Aluminium).
To improve the weight you can either
choose a material that is lighter
or one that is stronger, or one
that is lighter and stronger. Using
magnesium, which is lighter but
not necessarily stronger, you can
improve on weight slightly.
The problem with magnesium is two
fold: first - its fatigue properties
are poor and so are its corrosion
properties, so a wheel may not last
very long even if perfectly cast
and machined. The second problem
is worse - very often micro-porosity
occurs during the casting process,
which has a negative impact on both
fatigue life and corrosion. So magnesium
wheels can be nice and light but
may not last very long, sometimes
less than a racing season. This
makes magnesium wheels good for
racing but unattractive to the man
in the street. The only solution
is to find a lighter, stronger,
fatigue free and corrosion free
material - Carbon Fibre –
which, as an engineering material
is far superior to Magnesium or
Aluminium alloys (see subsequent
Q&A’s for its technical
properties to confirm this).
Q: What
do BST wheels include?
A: Wheels are supplied with:
- All internal bearings, spacers
and seals pre-installed
- External spacers, where required
- Air valves
- Cush drive (rear double-sided
wheels)
- Sprocket (rear double-sided wheels)
where required
- Sprocket carrier (rear double-sided
wheels) where required – additional
wheels can be purchased without
a sprocket carrier for race teams
or track day users
The wheels are delivered so that
the user can simply fit their tyres,
discs and go.
Q: How much safer
are Carbon Fibre wheels than standard
wheels?
A: Carbon Fibre wheels have been
in existence for some considerable
time and have been proven to be
safe when designed and manufactured
properly and, as with any wheel,
used within their design parameters.
One of the parameters is the maximum
static weight of the motorcycle
for which the wheels are designed
(BlackStone Tek wheels are designed
for motorcycles that weigh up to
280kg dry) and have more than adequate
strength and damage tolerance for
any usage within a road/street,
sport or race environment. Safety
is dependant on more than just strength,
though, and whenever a bike becomes
more easily controllable because
of better dynamic characteristics,
active safety is enhanced too.
Q: What
are the physical properties of Prepreg
Carbon Fibre that make it particularly
suitable for wheels?
A: Some of the properties of Carbon
Fibre composites as used in BST
wheels.
Material used - Carbon Fibre Prepreg
in a woven and unidirectional format,
embedded in a resin matrix, made
from toughened epoxy.
- Max structural temperature: 120
degrees C
- Min structural temperature: -40
degrees C
- Corrosion resistance: Totally
corrosion free
- Chemical resistance: Resistant
to most dilutants such as acetone,
benzene, thinners,
- Automotive fluid resistance: Limited
resistance to brake fluids and acids
- Density: Approximately 1.7 kg/qdm
(Aluminium 2.7, Titanium 4.5, Steel
7.9)
- Damage Tolerance: Similar to 2024
Aluminium
- Strength: Better than 2024 Aluminium
- Stiffness: Similar to 2024 Aluminium
Variable wall thicknesses can be
created anywhere as needed in order
to increase strength where required.
Fibres are oriented in the direction
of stress in order to increase strength.
Q: How much
stronger are BST Carbon Fibre Wheels
than conventional wheels?
A: BST Carbon Fibre wheels are comfortably
over-engineered for street/road
use and have undergone an intensive
programme of very stringent testing
to verify their design and to confirm
their strength and durability.
A designated test body in the UK
performed the following tests and
all tests were conducted on a single
wheel. It is important to note that
performing a ‘single wheel
test’ is not usual when checking
metal wheels, since due to metal
fatigue behaviour, a single wheel
could not withstand all the tests.
To allow for this weakness in metal
wheels, the test regulations actually
specify that using one new wheel
for EACH AND EVERY test is permissible
during which it is destroyed, whereas
in this case a single BST wheel
withstood ALL tests and was still
completely serviceable afterwards.
- Cornering fatigue: 100,000 cycles
at 530Nm
- Radial fatigue: 500,000 cycles
at 5200Nm
- Torsional fatigue: 100,000 cycles
at 400Nm
- Impact test: 337.5kg from 150mm
(JWL)
The front wheel was designed for
a 135kg static load and the rear
wheel for a 145kg static load (this
translates into a bike with a total
dry weight of 280kg). Modern sports
bikes normally weigh between 160-220kg
and race bikes rarely exceed 170kg,
so these static load design parameters
comfortably exceed normal conditions.
The Eurotype Test Centre has tested
the rear wheels where both conventional
and offset versions have been subjected
to cornering fatigue testing in
excess of 1,000,000 (one million)
cycles at 590Nm.
Q: Do BST wheels
have TUV certification?
A: Yes, they have TUV certification
for both their manufacturing facility
and for the wheels – GSXR1000
front and rears, Ducati 916-998
series and 748 front and rears.
TUV requires certification per model
and the following are currently
in process – Ducati 999, MV
Agusta, Honda CBR1000, 954, 929
RC51 (SP1/2), others to follow.
Q: How much
lighter are BST wheels than standard
wheels?
A: Standard wheels are have become
lighter in recent years anyway as
bike manufacturers fight for magazine
headlines and performance gains.
However, it is still possible to
make very significant weight savings.
GSX-R1000 wheels have been used
here as a typical example of a modern
sports bike as it has wheels that
are among the lightest. On older
bikes, the weight savings with BST
can even greater.
Weight Examples quoted here include
bearings, spacers, seals, sprocket,
cush drive, valves, but exclude.
discs & tyres
Standard GSX-R1000 wheel
weights
Front 4.360Kg
Rear 7.529Kg
BST with Aluminium Alloy
hubs wheel weights
Front 2.380Kg – weight saving
1.980Kg / 45% lighter than standard)
Rear 4.638Kg – weight saving
2.891Kg / 38% lighter than standard)
Total weight saving 4.871Kg
Q: How long
have BST wheels been in development?
A: One of BlackStone Tek’s
design engineers, Chris Adrian,
has been developing Carbon Fibre
wheels for nine years, some of which
have been used in GPs. This new
BlackStone Tek range of wheels has
been under development for over
2 years.
Q: What
is the difference between wet lay-up
and the Prepreg construction, as
used in BST wheels?
A: In a wet lay-up manufacturing
process, the fibres are positioned
in the mould dry and the resin is
applied with a brush. The resin
is mixed by hand and inconsistencies
can be found after mixing. This
is a relatively inexpensive process,
but the resulting part is normally
heavier and the Fibres can distort
during the lamination process meaning
the process is less controlled.
This method does not lend itself
to the Autoclave process which cures
the part under controlled heat and
pressure.
In the Prepreg process used to manufacture
BST wheels, the resin is applied
by machine onto the Fibres in a
thin film. Therefore, the resin
is very even and controlled. The
layers are laminated by hand but
can be positioned much more accurately.
The parts are then cured under a
high pressure and temperature environment
(Autoclaved). This results in a
well-compacted laminate with better
properties than with wet lay-up.
Laminate properties in Prepreg Carbon
Fibre can be 10%- 20% better than
wet lay-up at a lower weight (because
less resin is used to do the same
job). This Prepreg and Autoclave
process is perhaps more commonly
known as the process used to manufacture
the exceeding strong, but light,
chassis centres (often known as
‘tubs’) for Formula
1 race cars.
Q: How
long do Carbon Fibre wheels last?
A: Carbon Fibre wheels originally
made nine years ago by BlackStone
Tek’s design engineer, using
earlier and less sophisticated technology,
are still running today and there
have been no problems with any of
them. As Carbon Fibre is a fatigue-free
material, their lifespan should
exceed that for wheels manufactured
from alternative materials. Note
that the magnesium hubs on the full
race wheels are the limiting factor,
as the magnesium itself should be
checked for integrity every 2 years.
Q:
How much horsepower are BST rims
rated for?
A: BST wheels are safe up to 1900Nm
torque. BlackStone Tek uses the
torque measurement rather than horsepower,
as it is torque that is driving
the wheel. If your bike generates
more than 1900Nm of torque we would
like to see it, as a standard 2002
GSX-R1000 normally tests at around
99Nm…
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HPS
is the exclusive UK importer and trade distributor
for BST wheels. Dealers, please call for
prices and information.
CALL
0845 873 8254 TO ORDER YOUR SET TODAY!
...or CLICK
HERE to apply for finance securely online |
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*Finance
available subject to status. Images are for display
purposes only, actual product images may vary slightly.
Manufacturers' specifications and HPS prices are correct
at time of publishing and are in UK Pounds Sterling
(£); however, they may fluctuate and we therefore
reserve the right to amend them without notice. Prices
exclude delivery options which can be specified at the
customer's request. All manufacturer's trademarks acknowledged.
All products and offers are subject to availability
and HPS
terms and conditions of sale. Phone calls may be
recorded/monitored for training/security purposes. E.&O.E. |
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