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Downshifting &"Blipping" the Throttle
photographer: Kevin Wing
原文有詳圖說明
1. Downshifting smoothly on a sportbike, especially while braking hard from
high speed, requires a definite measure of skill and dexterity. In order to
avoid upsetting the bike, the engine rpm must be matched to road speed when
the clutch is fully disengaged, otherwise the rear tire will momentarily
"chatter" and upset the bike as the engine is forced to match road speed
involuntarily. This means that the rider must "blip" the throttle to raise
the engine rpm during downshifts-but he must do this while simultaneously
pulling on the front brake lever to slow down. While this riding skill is
obviously necessary on the racetrack, it can also pay big dividends in
street-riding situations where riding smoothly is a must; for instance, any
situation where you are cornering and braking at the same time.
2. The idea of blipping the throttle between downshifts can be intimidating
for the uninitiated, but with a little practice, the technique can soon
become second nature. First, make sure that your levers are adjusted so that
they are comfortably in reach of your fingers when sitting in a normal riding
position, and that your throttle is adjusted for minimal play in the cable.
The front brake lever should be angled downward enough to be easily gripped
with your hand in the closed throttle position. With the engine running in
neutral, try blipping the throttle slightly while pulling firmly on the brake
lever-note that it doesn't take much throttle movement to get the revs up.
Then practice simultaneously pulling and releasing the clutch quickly when
you blip the throttle (remembering to continue pulling on the brake lever as
if you were slowing for a corner).
3. The next step is to practice this technique while riding in a safe area
with no traffic. As you brake and begin your downshift, simply perform the
same practice drill as before, but add the act of downshifting. The action of
blipping the throttle and the downshift should be simultaneous and quick, and
it doesn't take a whole lot of revs to match the engine to road speed; unless
you're riding at racetrack aggression levels, all it will require is a slight
throttle blip. With practice, you'll know just how much is necessary at
various speeds. Note that mostly the palm of your hand handles the act of
moving the throttle because your upper body weight is centered on your palms
under braking anyway, and your fingers are busy actuating the brake and
holding the bar. All it takes is a slight wrist movement to blip the
throttle. You'll find this will help avoid affecting your braking action due
to influencing your fingers' grip on the brake lever.
4. If you find that you still have problems with this technique, try
adjusting your brake lever in so that it's easier to reach (without hindering
your ability to pull the lever in for maximum braking, of course). If you
still have trouble, you will have to employ the "non-blip" method many racers
(such as AMA perennial front-runner Eric Bostrom) still use. This simply
means the clutch is released gradually after the downshift so that the engine
rpms can progressively match road speed without the rear wheel chattering.
The downside is that the rider loses the added engine braking while the
clutch is disengaged and the bike "freewheels," and he must compensate with
the additional use of the brakes during this time. Also, it requires even
more skill at manipulating and controlling the bike while simultaneously
releasing the clutch lever slowly and gradually.