Engine
& Transmission: World class with Japanese
levels of Performance, refinement
and reliability.
Mighty strong opening statement from yours truly but a fact
nevertheless. It could have been very easy and simple for
Rajiv to have asked Kawasaki to supply the engine tech needed
but he preferred to strike out on his own. Notably because
he felt that Bajaj Auto had done enough to shore up on resources
- human and technological - to tackle such a feat. The early
brief called for a bike to be made just one rung up from
the Caliber but doing a 125cc model would not have been
the right thing with the genre and class of styling his
boys wanted to offer. Also the need to make a technological
statement via high Performance while retaining reliability levels was also kept in mind
while drawing up the brief for the engine design. The team
adopted a 'there's no substitute for cubic inches' criteria
and decided to make an engine which could be made in both
150cc and 180cc capacities. As they have turned out, the
150 and the 180 are misnomers because the lower capacity
unit displaces 143.91cc (with a near square cylinder dimensions
of 57x56.4mm) while the larger model is a 178.61cc, arrived
at by  punching
out the bore to 63.5mm while keeping the stroke constant
at 56.4mm. Keeping the engine internals relatively unstressed
was the key approach and surely they could have gone on
to high tech gizmos like a 4-valve head but then they didn't
want to make it a buzzing engine which would have hiked
the power for sure but placed it in the rarified regions
of the rev range rendering it almost useless for the bulk
of the populace. What the engine team led by Abraham Joseph
did was put in precise thought on detailing of the combustion
chamber, the intake manifold length as also the airbox volume.
In addition to that the move to a CV carburettor for both
engines was a move in the right direction not only from
the consistency of precise fuel delivery and crisp throttle
response but it also helped in meeting the tough emission
norms. The engine design team worked on the premise that
they didn't have to do something to clean up the mess but
rather design a unit which didn't mess up, especially in
the area of tail pipe emissions. I was surprised to note
that there is no hot tube, balancer tubes, air injection
etc on the Pulsar powerplant.
The Bajaj Auto boffins assured me that the bike meets the
emission norms without need for any add-ons. Joseph also
told me that much care was lavished on providing the right
stuff and the right stuff only and making sure that it worked
to deliver Performance. The
team was steadfast in its no-compromise approach and as
you can see they went in for the best ingredients to pack
up both powerplants. The pistons come from Shriram Pistons
who also provide the Riken rings. The CV carbs (26mm choke
size on the 150 and 29mm on the 180) come from Ucal Mikuni,
the all-aluminium engine is machined internally at the Chakan
plant and the only imported item on the entire bike is the
crankpin which comes from a Japanese firm. The bike runs
a very high - for India - 9:5:1 compression ratio and just
to ease out the physical aspect of kickstarting the bike
to life, Joseph's team has designed a very simple decompressor
on the camshaft which eases this important chore dramatically. Of course Bajaj
has designed the engine with an electric starter (available
as an option on the 150 and as OE on the 180) but the beauty
of the decompressor is there to savour and experience. And
then there is the balancer shaft placed behind the crankshaft
and features an indirect drive. The Yamaha YBX also features
a balancer shaft but ride the Pulsar and check out the NVH
or the refined nature of the power delivery and it will
be a revelation. If not done right, heavy balancer shafts
can be power sapping but the Pulsar engine has been designed
and perfectly tuned to a 'T'.
Bajaj also sussed out the ignition admirably without the
need to go in for an expensive digital configuration. Look
at the stylised exterior of the engine and the mechanically
inclined among enthusiast bikers will revel in the aesthetics.
But look closely at the cylinder head cover which is most
user friendly if ever any valve clearances were to be adjusted
or such. Let us focus on the power and torque produced.
The 150 is credited with a max output of 11.82bhp at 8500rpm
while the larger  180
with its big bore, short stroke config develops 14.74bhp
at 8000rpm. The bigger engine produces 13.2Nm of torque
at 7000rpm while its smaller sibling doesn't disgrace with
10.8Nm of torque made at the same engine speed. Point to
be noted is that the figures for bhp and torque produced
are measured at the crank. Just to put things into some
perspective, the Eliminator with its 173.9cc engine develops
15.2bhp at 8500rpm and 13.7Nm of torque at 7500rpm. Taken
with the dry weight in mind, the Pulsar sports a power to
weight ratio of 120bhp per tonne as compared to 97.44bhp/tonne
for the Eliminator. The point which Joseph drove home to
us on the engine is that they wanted to have the engine
spinning at low revs in the higher gears and aid the driveability
aspect, a luxury bikes from the other makers don't enjoy.
If you glance at the spec sheet, both Pulsars sport the
same internal ratios as also the primary and final drive
ratios. The onus was obviously on Fuel
Efficiency when the ratios were being finalised and
the low ratios (lower than those on the Caliber for instance)
do not stint on Performance while trying to eke out the Fuel Efficiency.
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