VOL. 51 ISSUE 19 MAY 13, 2014 P51
is only wimpish initially, at part
throttle: crack the twist grip wide
open, and after a sluggish initial
pickup, response becomes quite
strong – think of it as riding a
peaky four-stroke motor tuned for
top-end performance.
On the other hand, the aptly
named Sail has zero regen, so
it's like riding a two-stroke when
you back off the throttle and
the BMW keeps sailing (pun in-
tended) right along. This makes
it the preferred option when
climbing a twisty mountain
road where without any en-
gine braking it is much eas-
ier to get the C-evo flowing
effortlessly through succes-
sive turns, with just a touch
of front brake to adjust turn
speed to suit.
Finally, Dynamic is the
most aggressive mode,
combining strong accelera-
tion with maximum regen,
making it more suited to a
point-and-squirt riding tech-
nique, so ideal for descend-
ing a twisty hillside road,
or carving corners on level
ground. So each mode has
speed and TCA limits the mo-
tor's torque if a certain plausibility
threshold is exceeded – making
it a pre-emptive rather than reac-
tive system, triggered by an incip-
ient loss of grip at the rear. TCA
also serves to stop the rear wheel
from skidding when intensive re-
generative braking produces a
correspondingly high level of
drag torque, especially on slip-
pery road surfaces. Job done,
times two.
Another complaint we had two
years ago was that the rear sus-
pension wasn't very compliant -
the 4.5 inches of wheel travel at
either end seemed much reduced
especially at the rear, where the
single offset direct-action WP
shock (so, no progressive link)
mounted on the swingarm didn't
give very good ride quality. That
meant encouraging you to avoid
any bumps or patches in the road
surface, if you could.
Well, that's also been fixed
with a really noticeable improve-
ment in both ride quality and
compliance. Now you can go
looking for bumps, and the C-evo
will take them in its stride, aided
by the low center of gee that also
optimizes handling in turns of
what is quite a heavy package.
Countering the weight trans-
fer delivered by accelerating
and stopping a vehicle weigh-
ing 584 pounds plus rider/pas-
senger, while giving reasonable
comfort, must have been quite
a challenge, and BMW's engi-
neers have met it well – although
this electric scooter is only nine
its uses, and is very distinct one
from the other.
One feature we were surprised
not to find on the prototype two
years ago was any semblance
of traction control, which with a
device that delivers maximum
torque at 1 rpm is surely a vital
rider aid on a damp surface.
That deficiency has been ad-
dressed via the TCA/Torque
Control Assist program, where
the ECU monitors the rear wheel
The dash:
Everything you
need to monitor
things on your C
evolution.
