Kawasaki GPZ 600R vs Yamaha XJ600
Jan 1985
Monday evening. I handed back the Tenere to Yamaha
and squelched around their yard, my oversuit dragging
in the puddles and a trickle of water running down
my neck. I pondered on the reality of being a bike
tester and dreamed about being one in California,
where all you seem to need are leathers and a black
visor. Humph.
I was sad to see the big single go as it was such
a useful tool in these conditions, its torque making
it a real cinch to ride in the wet, and I wondered
if the four's claimed 72bhp was going to come in as
easily as the single's claimed 42 steady old nags.
Eventually they wheeled out the red and white XJ and
I hopped on board, perversely wondering how they could
afford to produce two machines for the 600cc four
stroke market. Perhaps they can't, which would account
for their recent financial state.
It seemed ludicrously small and compact after the
single's eyeball poppin' seat height and cartilage
poppin' tank. The XJ's bars were nicely set forward
and narrow, the footrests reasonably rearset and high
and the saddle slim but comfortable. Sitting in the
perfect position for getting on with it, tucked neatly
in behind the fairing, I cast off into the murk with
visor down, oversuit reefed in and mainbrace spliced.
With all hands to the bars and feet to the pegs I
was in second gear before clearing the yard. Whereditgo?
First gear is definitely low.
I was pretty unimpressed with it all as I bopped
home since it felt rewy and twitchy in the wet and
liable to spit me off if I got it wrong. Instead of
being able to use engine torque I was back to the
old game of fanning the gear pedal about four times
until something registered and then treading gingerly.
When I reached the A3 slip road, however, feeling
thoroughly heaved off, I drew a straight bead on the
dual carriageway and let it go from about four grand.
I didn't even know what gear I was in as the six speed
box had temporarily lost me.
By the time we hit the carriageway it was up to about
5000rpm and climbing, with the speedo swinging past
the 80 mark. I found another gear, a thousand rpm
lower, and got stuck in, the rain completely forgotten.
If the laws of the universe had permitted it the sun
would have come out.
A complete transformation from tedium to fun had
been wrought simply by twisting the throttle remorselessly
and keeping the revs up, and to an extent this is
how our relationship stayed. It was much more fun
being nasty to it than being nice, as is often the
way in this naughty world of ours.
You can't write it off as an all or nothing machine,
however, a Jekyll and Hyde. If you are just tooling
around, with the optional wicker shopping basket on
the front, it will happily pull from 2000rpm and simply
gets more frantic the more revs you pile on. There
is no big leap at any revs, but keeping it below seven
or eight thousand is advisable if you want to keep
the cauliflowers in the basket.
Personally I don't like constantly thrashing a machine
just to keep a good pace up so I tried changing up
at 6000rpm, which would drop the revs by 1000, and
winding it on. Bad move. Unless you have experienced
it you just would not believe the racket it makes
at SOOOrpm. The source of the din seems to be the
frame mounted half fairing, but the cause of it is
the vibration that sets in and only slowly clears
as the revs rise. It was irritating enough for me
to use the machine as an all or nothing, Jekyll and
Hyde bike, either staying under four or winding up
through to seven or eight. After about ten seconds
of that chainsaw buzz I would become so crazed that
I would just hit the throttle regardless, sending
cauliflowers in all directions.
This is all very strange since the XJ600 is based
on its predecessor, the 550, which was a pretty smooth
machine. The engine has naturally received a fair
amount of attention, and it can only be assumed that
not all of it was welcome. The four pots have been
pushed out to 598cc via a 1.55mm bore increase to
58.5mm and a stroke job from 51.8 to 55.7mm. Bigger
valves have been lobbed in, now 31.5mm inlet and 27mm
exhaust, operated by new higher lift camshafts and
the crank, conrods and pistons have all been lightened.
Despite the loss of the YICS swirl system, but with
10:1 compression and larger, 32mm carbs, the all black
engine churns out a claimed 72 geegums at a giddy
10 500rpm. Our dyno test pulled out 61bhp at the rear
wheel which is still pretty good for a 600 four with
'only' two valves per cylinder. The alternator runs
behind the crank which keeps engine width down to
a svelte 16in. It is a small, compact and powerful
unit.
It feeds through a six speed gearbox that seems positively
jam packed with cogs. Okay, so this is a revvy bike
but it's not as if the powerband is only needle wide
so I don't really see the point of six gears from
a practical point of view, especially as first gear
is so low you can easily pull away in second. However
they are all easy to find and upward changes don't
need the clutch, so you just have to resign yourself
to looking like Thumper every time you pull away from
a junction, your left foot a blur of motion.
It is just as well that you don't need the clutch
all the time, since it is a pretty stiff item. It
is stronger than on the 550 and certainly feels it.
I think part of the problem was confined solely to
our battered test bike, but it still didn't feel as
if that nice silky feeling was in there at all. The
same could be said for the throttle, and the choke
which needed two hands to turn, and twisted the whole
left hand bar assembly.
The dials are lifted from the XJ900, which should
keep production costs down, with the redline relocated
at 10 500rpm. The speedo is on the left with the tacho
in the middle and a fuel gauge on the right. The gauge
seemed surprisingly accurate and managed to resist
telling me too many flagrant fibs. The switchgear
is pretty good, with the shining star being Yamaha's
exemplary self-cancelling indicators, which I reckon
are the best in the known universe. The bar assembly
is rounded off, so to speak, by end weights: by now
we all know why they are there.
If the other departments have some grey areas then
the suspension is shining white. It is a neat combination
of well proven kit without the added burden and expense
of dubious techno whizzwozz.
Considering that this is Yamaha's mid-range charger
I am ever so slightly amazed that it is all so, well,
normal. I mean, look at those frame tubes: they are
actually black and round all over (as opposed to round
only where you can't see them, eh Suzuki?). They wrap
round the frame and each other until you have a good
solid frame on which to hang the suspendies. A good
start. Lester Harris of frame fame fails to see the
engineering advantages of square section frames and
I reckon that is good enough for me.
I wandered round the front end, my eyebrows raising
until they hit the back of my neck. Where were all
those hoses and castings for the anti-dive that make
the brakes spongey? Where were all those stick-on
letters — AIDS and so forth? Where were the
unlinked air caps that ensure the fork legs have different
pressures in even before they start to leak? All I
could see was a sturdy pair of forks with a brace
which actually looked like it might. And what is this
— an 18in wheel no less. How untrendy. Wandering
round to the rear I took in the excellent Monocross
rising rate rear suspension that seems to go on everything
these days — good thing too.
Despite its archaic spec sheet compared to this week's
bikes the XJ handles like the proverbial roller skate.
It has the big advantage to those of us with lazy
dispositions in that you can't spend hours setting
it up but you just have to get on and go. The only
adjustment available is in the rear shock, which has
adjustment for preload and nothing else. You can tinker
with the shock setting via a neat little toothed belt
and offset nut arrangement that means you can choose
any of the five settings without actually hurting
yourself or losing the skin on your knuckles —
that can be left for when you are walking along. Only
joking haha. Gulp.
Once under way what took me aback at first was the
speed of the steering. I'll admit to being more used
to large lumps that need constant wrestling to keep
under control (some of the bikes have been tough too),
so I started off by trying to steer with the bars.
Having nearly rammed the petunias on the first six
roundabouts I stumbled across I figured that maybe,
just maybe I was doing something a little wrong.
You can make it steer and twitch really easily so
just slight movements seem to be the answer with delicate
input from the botty English. When ridden properly
it has a lovely taut feel to it that convinces you
it is not going to get out of shape. You can slam
it around with relative impunity although large bumps
or series of them come right through and jar you off
line. The front forks seem to be the main offender
here, and the front jumped sideways every now and
then, but only if you were pushing hard and banked
well over.
Even at high speed it tracked steadily along without
having the suspension higher than position three,
and without that vague feel you often get with bikes
at speeds over the ton. This of course is one advantage
of having a bike weighing 460lb that is bowling along
at a rate that would keep most 750 owners happy.
You have to work a little harder than them of course,
especially if the road dictates plenty of drastic
speed changes (like if it's full of policemen). I
was finding I was often having to come down three
gears for corners and still being dumped at the wrong
end of the tach. Top gear is definitely no overdrive,
and would pull towards the red in a suitably determined
manner so long as you had over SOOOrpm dialled in.
The bodywork backs up this performance and looks
really vigorous in a slinky kind of way. The 4.18
gallon tank doesn't look that big but stays slim and
tucked in, leading into the shaped and comfy saddle.
The fairing blends into this line well, even though
it vibes a bit (despite rubber mountings) and dumps
wind and rain straight onto your patellas. Eek.
The tail section is the only real oddity, with grab
handles joined by what looks like old melted down
fork braces — ie tin. It is different, which
is what we are always demanding but to my bloodshot
eyes it is also a bit de trap, know what I mean John?
The tail hump holds the toolkit and a little velcroed
envelope for papers which was rather neat I thought.
At least you can keep your speeding tickets dry. You
get to this lot by undoing two catches and lifting
the seat off, a la CX, as it is not hinged.
The styling is obviously in the new Yamaha look,
seen on everything from the 350LC to the FJ1100, and
gives a good family continuity while also looking
dead smart. The fairing and belly pan are pretty much
the eye catching base of it all and, I am afraid,
the wallet catching. The fairing and belly pan total
£464. Keep this fact away from your insurance
agent and avoid getting too close to absolutely anything.
To do this is not difficult since the brakes are
pretty brill, being nicely progressive all the way
without needing excessive death grips on the levers.
The front pair of opposed piston discs are relatively
better than the rear and, considering there is no
anti-dive, there is little of the nose in the tarmac
act when you throw out all drag anchors.
This little package led me to start riding it really
hard. Maybe it is just my perverted sensibilities,
but it seems to beg to be thrashed and have its neck
wrung for hour after hour until you arrive at point
B having gone via the rest of the alphabet. I ended
up holeshooting bigger bikes, scraping me boots off
and generally having a shark of a time.
This behaviour knocked the fuel consumption down
to high forties from the mid fifties, but that is
still not a bad figure for such fun-filled abuse.
The only bad times were at night and, worse, in the
rain. I suppose you can't expect to have your best
thrills under these conditions, but the first time
I exceeded one hundred miles per measured hour on
her majesty's highway it started to go a bit strange.
The headlight was OK, if a little scattered, but suddenly
the fuel gauge started to blink rapidly. This was
really off-putting since it is a relatively big gauge
right in your line of vision. I was put off. When
I went to indicate at said speed the indicators refused
outright to stay on and I had to hold them on with
my thumb to ensure that everyone would know that I
was about to cut across their bows and ferret up a
slip road.
Both problems disappeared when I returned to legal
speed, but at high velocities you don't want any distractions.
Perhaps it is a built-in moral patrol device to warn
you of possible licence failure.
More serious was a ride away from the Bike Show at
Olympia in Friday night rain. Without an oversuit
I just wanted to get home schnell, but soon found
myself surrounded by coaches and cars bent on Friday
night destruction. Cutting through this dangerous
mass of jelly, my bulging eyes suddenly spotted the
red oil light flashing on. I instinctively went for
the clutch but had to just keep going to avoid being
run into the tarmac. I managed to pull into a fuel
station but could find nothing wrong in the oil department,
although there was plenty wrong with me by this time.
Assuming it was a short, I squelched off into the
rain with the light flashing all the way home, my
hands hovering on the clutch and my stomach hovering
all over the place.
Since it didn't reappear in the dry I can only assume
that it was a short, but that was the third instrument
to go on the blink, so to speak, not good at all for
a Jap bike and very bad for my English nerves.
Perhaps it was due to the vibes or perhaps it was
just our tired test bike, but surely that is how your
own machine is going to end up after a year or two
anyway — we just accelerate the ageing process.
For example, that neat four into two exhaust that
made such a nice noise was rusting where the black
pipes met the ally end cans, although the rest of
the system looked fine.
It was great fun to ride such a hard charger, although
it is also a practical pootler and tourer. It is a
rejativety-stralgmforward machine in both engine and
chassis departments so it might prove durable without
lazy bods like me having to do much more than get
on and go.
It is a serious shame about the vibes but that is
its only structural fault. A pretty good deal for
£2300 and at present top of the tree. Hold on,
who is this clambering up through the branches waving
a set of keys? Tis our Editor, fresh from the jaunt
at Jarama, with news of the GPz 600. Hum, suddenly
it seems a long way to the ground and I don't feel
at all secure.
Pillion Opinion
I do not really think that the XJ600 makes a very
good continental touring bike even though the saddle
is comfortable — if a little short and narrow
for us both. The problem was the footrests, which
gave me cramp in the legs after about 50 miles since
they seemed quite high and set to the rear. I also
noticed the smell of burning leather as my feet ended
up virtually on the exhaust pipes, which seemed too
close to the rests. Apart from burning them, the rests
also left my feet tingling from the vibration that
came through, particularly if it was revved hard.
The metal grab handles looked very smart but when
the rider accelerated hard for a small gap and I tried
to grab them I found that I couldn't get my hands
through them if I was wearing gloves as I usually
do.
I liked the speedo being on the left, where I could
easily see it for once, but I am not sure about seeing
the petrol gauge, since on a long run I could watch
it go down!
The bike felt very solid on the road and not many
bumps got through to me, so the ride itself is comfortable
and smooth. Generally I thought it was a fun bike
for up to medium distances although I don't think
we could carry too much luggage and I would demand
plenty of stops to rest my legs.
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