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Honda CB 750F

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Make Model

Honda CB 750F

Year

1981

Engine

Four stroke, transverse four cylinder, DOHC, 4 valve per cylinder

Capacity

748 cc / 45.6 cub in.
Bore x Stroke 62 x 62 mm
  Air cooled
Compression Ratio 9.0:1

Induction

4x 32mm keihin carburetors

Ignition  /  Starting

CDI 
  Electric

Max Power

57 kW / 77 hp @ 9000 rpm

Max Torque

77,4 Nm / 57.0 lb-ft @ 8000 rpm

Transmission 

5 Speed 
Final Drive Chain

Front Suspension

Adjustable telehydraulic fork. 

Rear Suspension

Swinging arm fork with adjustable shocks absorbers.

Front Brakes

2x 276mm discs

Rear Brakes

Single 297mm disc

Front Tyre

3.50 H19

Rear Tyre

4.50 H17
Trail 115 mm / 4.5 in
Wheelbase 1520 mm / 59.8 in
Seat Height 790 mm / 31.1 in
Ground Clearance 140 mm / 5.5 in

Dry Weight

230 kg / 507 lbs
Wet Weight 251 kg / 553.3 lbs

Fuel Capacity 

20 Litres / 5.2 US gal

Consumption Average

37.8 mpg

Standing ¼ Mile  

12.4 sec / 172 km/h

Top Speed

198.3 km/h / 123.2 MPH

Road Test

Cycle 1980
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 The Biker 1980

There's a tennis club quite close to where I live and every time I walk past the courts I can't help thinking just how bad the players are. The problem, you see, is that I don't play tennis and the only time I get involved with it is when Wimbledon comes round and, like everybody else in the UK, I get hooked on watching it on the box. So the only tennis I see is when guys like Borg and Connors are playing and they're so damn good they make it look easy. And that, dear reader, is the point of this preamble. The mark of a true professional is to make something difficult look easy.

Which, in turn, brings us to the Honda CB750FA, the latest in three-quarter-litre hardware from the men who brought you such diverse delights as the Benly, the Black Bomber and the lovely Dinah May.

This bike is just so good in all departments and so proficient at everything it does that it is all too easy to take it for granted.
Honda's 750cc, four-cylinder concept has been around since 1 969 when it was heralded as the world's first mass-produced superbike.'

The original single overhead cam, four-piper models were developed over the years and eventually culminated in the twin-cam K7 of recent memory while along the way there have also been the more sporty sohc F1 and F2 versions. Actually, developed may be the wrong word to use in conjunction with some Honda 750/4 models because at times it did seem as though Honda had lost their way with the big fours.

The original K models were tourers, while the F models weren't too sure what they were and at times it was quite obvious that Honda was having an identity crisis with the 750.

But now comes the CB750FA and for once you get the feeling that Honda have given the bike a distinctive personality of its own in spite of the fact that it was cloned from its big brother the CB900F. Ranged alongside rival 750s, the new FA is no longer the almost anonymous bland package it used to be.

At the heart of Honda's CB750FA is its new twin-cam engine, first seen on the K7 model. That particular version punched out 77bhp at 9000rpm but the FA's new four-into-two exhaust system has upped that by a further 2bhp.

The two camshafts drive no fewer than sixteen valves through buckets and replaceable shims which, as they ride on top of the buckets, can be replaced without having to remove the cams. Apart from its similarity to the CB900 motor, the FA also shares things like valve diameters and angles  and even some of its valve train equipment  with the six-cylinder CBX. Nothing like keeping it in the family.

As in the CBX, the FA's cams are driven by two Hy-Vo type chains complete with their own tensioners. One chain drives the exhaust cam from the crankshaft while the other loops round both cams to drive the inlet cam. Visually the FA motor is identical to that no oil cooler on the smaller bike.

It's on the road that the Honda's engine really proves its worth. The engine almost always starts at the first punch of the button thanks to electronic ignition. The handlebar-mounted, car-type choke needs to be used for a minute or two while the engine warms up and then you're on your way.

The basic characteristic of the motor is its uncanny smoothness and the best thing about the FA is the total absence of any power band. The throttle rolls back gently and the power comes in with the smoothness of a fast-flowing river. There aren't any flat spots either, you just keep winding on the revs until at around 10,000rpm the engine finally runs out of puff. Its flexibility is hugely impressive; roll-ons, even from low revs, are achieved with no snatch or spluttering.

There is an ironic twist to the story at this point, however. The original K1 Honda CB750 produced 67bhp and was capable of about 1 20mph. The FA produces 79bhp yet at the MIRA testing grounds we could squeeze no more than 120.39mph out of it.

A careful tuner might be able to find another 3 or 4mph but that's about it. The reason for its loss of speed is the fact that over the years the exhaust emission controls have gradually strangled the life out of the big motor. The modern day Honda is also heavier.

In all other ways, however, the FA is a superior machine to any of the 750/4 variations that have proliferated over the years. And it's the handling department in which the FA is most noticeably improved. The FA uses a duplex cradle frame, identical to that of the CB900, and sturdier than almost anything the Honda company has produced for a big bike yet.

Where the FA does differ from the CB900F is in the suspension set-up. The 900 uses air forks, but on the FA the front fork is a conventional oil damped telescopic. In fact, the 1981 US 750s have air-assisted forks so we can expect the same here shortly, I imagine.

The rear suspension however, is a lot more complicated. This utilises the FVQ dampers, first seen on the CBX, which have, in addition to the normal five position spring preload arrangement, three-level rebound damping and two-level compression damping.

The rebound is altered by turning a slotted ring at the top of the unit, while the compression is adjustable by means of a lever at the base of the damper body.
On the road the CB750 proved beyond doubt that it is  with the possible exception of the 900 which I haven't yet tried  the best handling big bike that Honda have ever made. It is comfortable to ride, easy to steer, swift to react to directional changes and comes to a stop in a very positive manner. It feels good to ride and the Bridgestone tyres seem to be able to cope with all but the most lunatic of lines.

The clutch is light, the gearshift slick and the engine characteristics so smooth that the FA encourages you to keep riding it all day. And with fuel consumption at around 45mpg it is fairly economical.

Complaints? A couple, and irritating ones they are too. The FA's front discs still need constant pumping in the wet and, secondly, Honda have chosen to fit a new type of rocker indicator switch. You press it to indicate one way and slide it to indicate the other. It isn't as bad as the imbecile version fitted to the H100A but it's still poor.

The photographs you see on these pages were shot in the Derbyshire dales.This meant a pre-dawn start in mist and pouring rain, a long blast up the M 1 in the dark and wet and then endless runs round the hills so that photographer Michael B could do his thing. Stop, start, blast, stop mercilessly, again and again.

Then came another long hard run down the M1 in the dark and a ride right through London's heavy traffic until I eventually arrived home. The bike hadn't missed a beat and it had coped perfectly with the most abysmal conditions. It had got the job done and made it look easy. And that is professionalism.

Source The Biker 1980