HONDA 750
Tales
from the past
1977
saw the birth of the Honda 750F2, the last UK model that had evolved
out of the original, late sixties, CB750K1. All the bikes used the
same basic SOHC engine that in some peculiar ways was a throwback to
the abortions of British engineering, featuring, as it did, such
antique items as a chain primary drive (albeit, a very strong hy void
job that didn't wear very quickly - just as well as a total engine
strip was needed to fit a replacement) and a separate oil tank. Okay,
it was relatively smooth and had an electric start to aid bikers
maimed by British bikes; it also tended to stay together pretty well.
As
the K1 got older, it became heavier and slightly more stable. By the
time the K7 arrived it was outclassed by several rival fours of
superior design and power output. In a not typicality Honda manoeuvre
the F1 was introduced with a new euro-style, a lot of hype and a
slightly tuned motor that almost ruined Honda's reputation for
durability by self destructing with apparent ease.
The
F2 had an impressive package of modifications, not least a detuned
motor that stopped it falling apart, almost meeting the standards of
durability found in their first four. Although it may not be so
impressive that Honda had to make the bike go slower to be more
reliable, at least the rider was ensured of some kind of peace of
mind; not until the completely new CBX750 was introduced did Honda
get back into the right frame of mind that produced the best
bikes although tales of burnt out exhaust valves in these models does
show that four valve technology is still not fully understood.
Despite
the lack of ultimate top speed (down 5mph to 120mph) the F2 did
feature higher lift cams, widened ports and bigger valves, which
managed to produce 69hp at a mere 8500rpm. The F2 weighed in at
4951bs dry.
The
F2 is the nearest that Honda came to perfecting the CB750 formula.
The real cutting edge was achieved when the older motor was
stuck in a decent chassis, Dresda, in particular, shaving off around
a lOOlbs, allowing a stock motor to increase performance and maintain
reliability - at the expense of an uncomfortable cafe racer
riding position.
An
immediate problem apparent on the F2, especially in the damp,
wet riding days of the UK, is that the front brake doesn't work in
the wet. The F2 did have an extra disc fitted, which considerably
improved braking in the dry.
Swapping
the stock pads for types specifically designed for use in wet weather
made not one iota of difference. In fact, so bad did these brakes
become in my mind that they stood right out from the rest of the
machine which exudes a feeling of dependability. Naturally, when
these very same brakes seize up their calipers the temptation to
start bashing the whole affair with a large hammer is very hard to
resist.
Whilst
the bike is far from being a lightweight, town riding was no
real hassle if you were willing to put in a bit of effort. At least
the large wheels didn't suddenly flop into slow corners like 16
inchers. Engine width was more of a constraint when flicking through
cars than the actual mass of the machine. The bars are usefully wide
for exerting pressure at low speeds, but a touch too high and wide
for comfortable high speed cruising. On very long journeys this can
conspire with a heavy throttle and a wide seat that digs into the
thighs to make things less than perfect.
Really
fast hustling was rather inhibited by a speed wobble around llOmph
and a shower of sparks in left-handers from the centre stand tag
digging in.Changing
direction in fast corners needed mucho muscle and stability went
for a long walk if you jammed on the brakes when in the middle of a
corner, although a bit of moderate engine braking by shutting down
the throttle was a relatively safe way of losing speed.
When new, the suspension gives a
ride that approaches excellence, and the suspension exhibits an
uncharacteristic amount of damping effect - way ahead of the
sixties stuff and not that far short of the very modern components.
Of course age is never kind to Japanese suspension - by the time the
warranty has expired, and the better Wop stuff has just bedded in,
the F2 suspension has to be fettled with, at the very least, the
good old stand-by of heavier fork oil and Koni rear shocks.
At least twin shocks are devoid of
quick wear linkages and nasty maintenance problems. The motor,
itself, has been remarkably free of trouble, maintenance mostly a
case of checking rather than actually adjusting. This is only as it
should be, because by Japstandards
it's no powerhouse, but in return for a lack of excess of top end
madness there's a commendable middle range punch that makes the bike
a pure joy to hustle along fast A roads.
No engine is totally free of
problems, though, and the F2 will soon start giving trouble if
regular oil and filter changes are neglected. Every 1000 miles would
be a good starting point for oil changes. If you don't do this,
and use the bike hard, you'll end up rebuilding the whole top
end. Expensive. The clutch is a little notorious for rattling and not
quite as strong as it ought to be - but moderate use causes no harm.
It's also worth checking the motor on the overrun, or when changing
down through the box, for white smoke out of the exhaust - a
sure sign that the valve guides are on the way out
- something that can happen from 20,000 miles on.
A big plus in owning any i CB750
is the interchange- ability of the various parts of the different
versions of the bike. This compensates for the extortionate cost of
factory and, to a slightly lesser extent, pattern parts. Not
that this was much of a hassle as the most expensive problem I had
was replacing the rotted exhaust.
A
fair bit of persuasion was needed as the Motad 4-1 was really
designed to fit one of the K series. It's just that it was going
cheap One of the problems of owning
a bike with an engine designed ten years before the current
noise and exhaust legislation is that the engine is adapted rather
than designed with these constraints in mind - thus fuel consumption
could be a pretty frightening 35mpg, although it did average 50mpg
and even did a best of 65mpg on occasion. By way of compensation,
the oil consumption was negligible.
HONDA 750 |
The
F2 doesn't come fitted with a kick-start and when the battery goes
dead it's a very heavy bike to push start. Also the silver in the
headlamp faded to such an extent that night-time riding became very
dangerous - it was cheaper to fit a pair of bolt on spots than buy a
Honda unit! The speedo was wildly optimistic - an indicated 140mph
was really only 120- 125mph!
These are minor quibbles, on the
whole the bike was a great all-rounder, dependable almost to the
point of boredom. Not exactly a plodder, but then not really a
scratcher either. A good bike for touring. Less weight, proper
front brakes and a little bit more power would have made it a real
winner.
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