 The
fine-tuned Libero and CT 100 engines are both near-vertical
and similarly configured. They are both four-stroke, air-cooled
and single-cylinder units that use twin valves driven off single
overhead camshafts.
Throughout the road test, we noticed both these lean-tuned motors
require a hint of choke to clear their throats and begin their
day. The G5's larger-capacity unit is neater in enclosing its
oil routes. It has a large sump and a cast iron cylinder that
displaces 106cc. Dimensions remain undersquare, with bore and
stroke measuring 49mm x 56mm.
Peak power developed is 7.6bhp at 7500rpm and peak torque 0.8kgm
at 6000rpm, slightly lower than the CT 100’s figures of
8.2bhp at the same rpm and 0.82kgm of torque at a more useful
4500rpm. Breathing for both motors is via conventional carburettors
and air-filter units. The Yam engine feels hyper-refined and
clips the Bajaj’s wings in this department. Slightly smoother
and quieter operation aids this department. At the same time
both engines are satisfactorily vibration-free and do not suffer
any flat-spots or hiccups no matter what the situation. Both
bikes have exemplary clutch feel and smooth four-speed gearboxes
that shift via heel-and-toe shifters. The difference is in the
patterns—the G5 shifting 1-down and 3-up, to the CT 100’s
4-down pattern.  While
the G5 now injects fresh air to clear its exhaust up, the CT
100 exhaust system has received a catalytic converter.
The new CT 100's motor has roller bearings engineered on its
rocker arms for friction cutting. Its bore and stroke dimensions
are 53mm x 45mm making it short-stroke. Initial torque delivery
is assisted by the addition of a resonator as first seen on
the Discover Specifications list—Bajaj’s
exhausTEC. The engine is knock-proof, with peak torque made
1000rpm lower than on its ancestor. Changes have also been made
to the sprocket teeth to compensate for the smaller rims. Other
than this, the engine remains identical to that seen on the
earlier CT100. The familiar blue ride-control switch that checks
heavy-handed throttle users when switched on is carried forward
to the new CT. We preferred to switch it off and modulate the
throttle as per our requirements.
Performance for both these fuel-efficient
bikes is as good as any other bike in this segment. Acceleration
tests on the CT100 recorded 0-60kph going past in 8.08 seconds,
while the same speed test took 8.99sec on the G5.
|
September
2005