American Motorcycle Dealer AMD 247 February 2020 | Page 28

NEWS
'Revival Birdcage' by Revival Cycles, Austin, TX
BRIEFS
The 95th edition of the FIM
International Six Days Enduro
will be staged at Rivanazzano
Terme, Italy, on Aug. 31 - Sept.
5. 2020. The longest running
world championship in
motorsport, the 2019/94th
edition in Portugal saw a win
for the U.S. Women's World
Trophy team with the American
XC Gear team taking the Club
division and the U.S. Junior
World Trophy team finishing
runners up. The USA last won
the World Trophy title in 2016 -
its first ISDE world title.
Motorcycle racing legend and AMA
Hall of Famer Dick Klamfoth has
passed away, aged 91. Born in
Columbus, Ohio, Klamfoth began
riding motorcycles at the age of 14.
He won the DAYTONA 200 on a
Norton in his first outing in 1949 and
following that up with additional
victories on the beach course in 1951
and 1952. From 1954 to 1961,
Klamfoth made his mark on the
GNC, finishing in the top 10 each
year and scoring five national Half-
Mile wins on his BSA. Klamfoth's
record of three DAYTONA 200
victories held for nearly 50 years, but
the "King of the Beach" will be
synonymous with America's most
historic motorcycle race forever.
The AMA has named Brit Hayley
Bell as its 2019 Motorcyclist of
the Year. Founder of the Women
Riders World Relay, the AMA
says it is recognizing her
activism in calling attention to
the needs of women riders and
for creating a worldwide
connection among them. The
WRWR has members in 84
countries and seeks to
demonstrate to motorcycle
manufacturers and makers of
riding gear that "female riders
are a formidable and growing
market that deserves their
attention."
aluminum pistons with two
compression rings and an oil wiper
ring. The running surface of the light
metal cylinders is coated with NiCaSil.
Lubricating and cooling oil is supplied
by a wet sump lubrication system with
a two-stage oil pump via sleeve-type
chain driven by the crankshaft. Classic
OHV valve drive with two camshafts,
as in the legendary R 5 to R 51/2, are
combined with modern 4-valve
technology and dual ignition.
Classic OHV Valve
Train with Two
Camshafts
Although the new 'Big Boxer' has four
valves, dual ignition, a modern
combustion chamber architecture,
intake manifold injection and the
BMS-O engine management system
for best possible torque and optimum
consumption and emissions, it uses
the classic OHV configuration for its
valve drive.
When developing the valve drive for
the 'Big Boxer', BMW says its
engineers "were inspired by a very
special engine design in the history of
BMW Motorrad – in keeping with the
heritage concept: the 2-cylinder boxer
engine of the R 5/R 51 (1936 – 1941)
and R 51/2 (1950 – 1951), the latter
having been the first BMW motorcycle
with a boxer engine after the Second
World War. In contrast to other OHV
designs by BMW Motorrad, this engine
– highly valued by connoisseurs – has
two camshafts driven by the
crankshaft via a sleeve-type chain.
"As in the historical role model, the
two camshafts are also positioned to
the left and right above the crankshaft
in the 'Big Boxer'. The advantage of
'Departed' by Custom Works Zon,
Shiga, Japan
Polaris has appointed Victor M.
Koelsch to its newly created role of
Chief Digital Officer. The new role is a
response to "technology and
customers’ digital expectations
evolving faster than ever," with
Koelsch owning the digital strategy
for the company.
28
AMERICAN MOTORCYCLE DEALER - FEBRUARY 2020
this "twin camshaft boxer" is the
shorter pushrods. This also makes for
reduced moving masses, minimized
deflections, lower linear expansions,
and a generally stiffer valve drive with
improved control precision and higher
speed stability.
Fork Rocker Arm,
Anti-Hopping Dry
Clutch
In the traditional BMW boxer design,
the two pushrods actuate one pushrod
per cylinder side for the intake and one
for the exhaust side, guided in a sealed
pushrod tube on the top of the
cylinders. The two intake and exhaust
valves in the cylinder head are
actuated in pairs via fork toggle levers.
In contrast to today's widespread
engine technology, valve clearance
compensation is not effected by
means of hydraulic elements, but – as
was the case in most classic air cooled
BMW two-valve boxers for decades –
via one adjusting screw with one lock
nut for each valve. As was formerly the
case in the classic 2-valve boxers, valve
clearance adjustment (0.2 – 0.3 mm)
in the R 18 'Big Boxer' is also achieved
very quickly. The valves are made of
steel, with a disc diameter of 41.2 mm
on the inlet side and 35 mm on the
outlet side. The valve angle is 21
degrees on the inlet side and 24
degrees on the outlet side.
As in most BMW Motorrad boxer
engines for decades (with the
exception of vertical flow, air/water
cooled boxers since 2012), a single-
disc dry clutch transmits the torque
generated by the engine to the
transmission. For the first time it is
designed as a self-reinforcing anti-
hopping clutch, thereby eliminating
unwanted stamping of the rear wheel
caused by engine drag torque in the
event of hard downshifting.
The constant mesh 6-speed
transmission is located in a dual-section
aluminum housing and is designed as a
4-shaft transmission with helical gear
pairs. The gearbox input shaft with lug
dampers drives the two gearbox shafts
with the gear wheel pairs. An output
shaft is provided to bridge the distance
and reverse the direction of rotation. A
reverse gear is available as an optional
extra. This is driven by an intermediate
gear and an electric motor and can be
shifted manually.
Open Shaft
Secondary
As in all BMW motorcycles with boxer
engines, torque is transmitted from the
gearbox to the rear wheel in the R 18
via a propeller-shaft or universal-shaft
drive with universal joint, shaft and
rear-axle drive with bevel and ring gear.
The propeller shaft and universal joint
are examples of fascinating classic
motorcycle technology since they are
nickel-plated and open, as was
commonly the case in BMW Motorrad
models up to and including model year
1955. A so-called 'tripoid' joint is
applied on the gearbox side for the
purpose of length compensation.
Loop Frame
The Concept R 18/2 has a loop frame,
teardrop fuel tank and a "classic and
elegantly showcased universal shaft,"
cast iron 19" front and 16" rear wheels,
high-performance Brembo brake
calipers and Hattech stainless steel
tailpipe system.
Multitude of
Possibilities
BMW claims that the Concept R 18/2
puts forward a new interpretation of a
dynamic performance cruiser that not
only taps into an area previously
unexplored by BMW, but also
demonstrates the true versatility of the
'Big Boxer' platform. "After the BMW
Motorrad Concept R 18, our aim with
the Concept R 18/2 is to demonstrate
how flexible the basic engine and
suspension are as a starting point for
customization, and how easy it is to
authentically realize different styles.
And I have to admit - we were very
impressed at how it was possible to
bring this boxer concept forward from
the 30s via the 80s into the 2020s,"
says Bart Janssen Groesbeek, BMW
Motorrad Vehicle Designer for the Big
Boxer Concepts.
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