R&D GENIUS THROTTLE BODY
Instead of a flat slide or a butterfly, R&D designed
an elliptical barrel that rotates inside the throttle body’s
venturi. The elliptical barrel rotates completely out of the
way at full throttle, and because of its smooth shape, the
air flows over it with less disturbance.
VERDICT: Every MXA test rider liked the throttle
response of the Genius on both our CRF450 and YZ450F.
It smoothed out any irregularities, boosted horsepower
and made the bikes easier to ride. It was a clear-cut
improvement in the brain-to-throttle equation.
DIGITS: $1499.00 (throttle body
kit with Vortex black box)—
A slipper clutch
is a clutch that
pulls itself in when
it recognizes deceleration. A slipper clutch is
designed to lessen engine
braking, reduce wheel hop
and improve suspension performance.
VERDICT: We loved it. It made the bike freewheel
like a two-stroke. We could carry more speed into
corners. Throttle pull felt lighter, and hook-up was better
at roll-on. Plus, wheel hop was virtually eliminated. It is
technically a clutch, but it is more of a suspension device
than an engine mod.
DIGITS: $1674.99 (basket, inner hub/pressure
plate kit, fibers, steel plates and clutch cover)—
www.hinsonracing.com or (909) 946-2942. ❏
TRIGA IBOOST 2 THROTTLE
The Triga iBoost2 is a sleeve, butterfly and butterfly
shaft that reduces the throttle body’s venturi tube to
increase fuel velocity.
VERDICT: We wanted more mid from our KTM
350SXF, and we believed that going to a smaller venturi
would make the bike easier to ride. It neither gained
nor lost horsepower on the dyno but felt torquier, albeit
slower, on the racetrack. Half of the MXA test riders
liked it and half didn’t. Overall, it
made the 350SXF easier to ride
at a lower rpm.
(throttle body kit),
$119.95 (tuning tool)—
(951) 738-8050 or
kit gives you the braking
power of the pros.
VERDICT: The Tsunami oversize
kit offered abundant braking power with plenty of mod-
ulation. If you think the OEM brakes on your Japanese-
built motocross bike are good, then never ride a KTM.
If you do, you’ll be ordering a Galfer Tsunami oversize
rotor the next day. The quickest way to bring KX, CR,
RM or YZ brakes up to modern standards is with an
DIGITS: $371.00 (rotor, bracket and brake pads)—
(805) 988-2900 or www.galferusa.com.
USED IT, ABUSED IT, MISUSED IT & LOVED IT