Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/126784
Without bodywork. a heavily modified frame is revealed. Note lack of
backbone tube and steering head.
Front wheel comes from Interceptor 750 and modified for centerhub steering. Because of wheel
design. turning is limited.
Lower arm bears most of the stress
in RADD system; upper arm and
kingpin are very light in comparison.
vered that the ELF has about two
inches of travel."
After working everything out on
paper, Parker began the real work
late last year. The test-bed for the project was an 'S3 Honda XL600R
Parker began cutting, welding, machining and fabricating in October
and didn't stop until December. The
first ride was in January. According
to Parker, everything worked as
planned. "The front end is plush,
with six inches of travel. Steering is
very light. We started out using a
steering damper because we didn't
want to do any tank sJappers down
the road, but we got rid of it because
the front wheel didn't even wobble,
no matter what we did."
To achieve the bike's final form,
Parker began cuttingo£[ frame members from about the top of theeylinder
head on up. Gone were the steering
head and backbone; bye-bye forks. In
their place new tubes and gussets
were welded to accomodate the lower
and upper arm pivots. In place of the
frame backbone, a steel box was welded up; it bolts to the frame and doubles as the gas tank and steering head.
Since no stresses are transmitted to
the sleering head, the box/tank is
made of thin gauge material.
Unlike previous center-hub steering desigTls with pivot and control
linkages inside the hub, Parker's system has a large pivot - a kingpin achoring at the axle and just beyond
the circumference of the tire. It's
connected by ball joints to a short
upper A-arm and a longer lower arm;
a telescoping steering column attaches to the top of the kingpin where
it meets the A-arm.
The steering head and A arm run
on ball bearings, while the lower arm
and wheel rely on tapered rollers. AMoto-X Fox single shock has been
specially modified by Fox to fit the
system and ha a remote reservoir.
The complete assembly has a steering
angle of 27° with 3.6-inches of trail.
~ar}