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You have to work at turning the Yamaha. To turn right, you pull on the right handle bar, like so. Hanging off would help, too.
both
the
s are
. and
lying
the
twin
gine
g the
ood
split
ono
. We
but
ced,
gear
lonj;t
ways. Each shift was somewhat
indefinite and often accompanied by a
clunk. There were some false neutrals,
and one of the mos' elusive real neutrals
ever, The clutch is huge, powerful,
capable of resisting thrashing,
insensitive, grabby, and dangerous when
cold. It could not be made to slip after
repeated burno~ts. But when you
wanted it to slip that was difficult, t.oo.
The Norton has four speeds which
are adequate for the power band and
the. nature of the beast. Anyone who
wants to shift a Norton a lot is crazy.
The four ratios fit very well and the
overall ratio is really tall. At 75 MPH it
loafs at 4,200 RPM. Shifting is light and
easy and the throws seem to have gotten
shorter. There was never a missed shift
and neutral was simple except after a
thorough thrashing. The Norton's dutch
is weird. It grabs just a little less than
the Yamahas as it engages. In order to
make a smooth getaway it requires that
you pull it back in a little just at the
right moment. Its pull is easier than the
Yamaha's and it is easier to use.
However, after repeated bumouts
(which are so fine to do on the Norton)
it would begin to slip. Obviously, the
English don't make burnouts a common
practice.
Unlike the Yamaha, the Norton
connects its crankshaft to its non-unit
gearbox construction via a chain. So,
there's a chain to hassle with on the
Norton. However, the Yamaha has a
ch ai n to operate its omni-phase
balancer. The Yamaha chain did not
seem to have proper tension as that
seemed to be the source of somewhat
excessive mechanical clatter. It was
enough that we were convicned, for
three thousand miles, that the Yamaha
was about to blow up. It never got
worse and the TX-750 never faltered.
The real differences in the engine
units comes down to development
versus technology. The Yamaha was
created the way it is and will stay
mostly the way it IS. The 850
Commando is so different than its
ancestor, the' 750 Atlas, (and several
other, smaller twins) as to defy
comparison. People, real live human
beings, have ridden .around on the
Norton and tried to think up ways to
make it liveable (which the Atlas was
not). Though the Yamaba was no doubt
created by a man or men, it was also, no
doubt, cQ.mputer inspired, too.
Theoretically the ~ngine should not
make much vibration. But, there was no
one there to tell the computer that
tingling buzzes had much more effect
on human beings than sensual throbs.
The Norton shakes at low RPMs but the
shakes add to its characteT. Above 3,000
RPMs it is the smoothest bike we've
evet: ridden, period. It is uncannily
glassy. The Yamaha buzzes a little here
and theTe, but never makes any
vibration anywhere near the magnitude
of the Commando's low RPM shake. It
just buzzes away as the omni-phase
balancer and the piston play add and
subtract and occasinnally come up at
other than zero. When it does you are
all too aware of it.
The Norton is faster than the
Yamaha. It has 75cc more than the TX
750 and weighs at least 80 pounds less.
No surprise. But, the Yamaha produces
an equal amount of t!,rque and requires
no more effort to climb hills two-up. It
just doesn't motor as quickly. While the
Norton produces ail almost thrilling
surge, the Yamaha just goes. Then again,
if you're looking for speed the 750
Commando is quicker than either. In
side-by-side competition the 750
Combat we had around would fairly
trounce either.
Both bikes come with twin
carburetors. The Yamaha has Solex
license Mikuni, constant velocity,
diaphram items. The idea is to deliver
just as much throttle opening as the
engine desires (cbosen l:iy ambient
pressure depression in the ma"ifold),
rather -than linking throttle opening to a
rider's insensi·tive hand. Sure enough,
they don't really work very well. While
they offer excellent medium to high
speed metering, they don't respond
adequately to small throttle openings.
When you've got the Yamaha leaned
over with the stands dr..gging, and you
know that the lack of cush hub is going
to cause a snaP when you roll it on, you
want subtle throttle control. There
seems to be a rapid pressure change in
the manifold as you start to roll it on,
and whamo, the carbs let the engine
have it_ I't can be disconcerting, and also
makes the bike very difficult to ride
smoothly around town. The' butterfly
choke plates, combined with a quick jab
with the right thrumb, make starting an
easy task.
The Norton carries a couple of A~
Concentrics of. 32mm measure. The
carburetors were not a thing of joy and
beauty on the Norton. Like the
Yamaha's carbs, they supplied superb
medium to open throttle measure. Like
the Yamaha's carbs, their low Tange
performance was not what it seemingly
could be. The N orton liked to flu tter
and miss at constan t throttle opening
below one-half. At no time did they feel
like they were adeq'Jately
complimenting the Norton's low end
torque. Because of a compression ratio
that is over a point lower than the 750
Combat Commando, starting was not
too difficult_ It was still a little
embarassing to have to fl:ail at the kick
starter lever when all those around were
giving their thumbs a workout.
The Amals put a grand finale On their
lackluster performance by leaking more
.
-,
..
