Laverda 750SF2

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File:Laverda-750-SF2-74--1jpg
Laverda 750SF2
Manufacturer
Production 1974 - 75
Engine
Four stroke, parallel twin cylinders, SOHC, 2 valve per cylinder
Compression ratio 8.9:1
Ignition Bosch electronic
Transmission 5 Speed
Suspension Front: Ceriani telescopic forks
Rear: Swinging fork, Ceriani adjustable shocks
Brakes Front: 2x 280mm discs
Rear: Single 280mm disc
Front Tire 3.50-18
Rear Tire 4.0-18
Wheelbase 1452 mm / 57.2 in
Seat Height 790 mm / 31.1 in
Weight 215 kg / 474 lbs (dry),
Fuel Capacity 19 Liters / 5.0 US gal
Manuals Service Manual



Engine[edit | edit source]

The engine was a Air cooled cooled Four stroke, parallel twin cylinders, SOHC, 2 valve per cylinder. The engine featured a 8.9:1 compression ratio.

Drive[edit | edit source]

Power was moderated via the wet plate.

Chassis[edit | edit source]

It came with a 3.50-18 front tire and a 4.0-18 rear tire. Stopping was achieved via 2x 280mm discs in the front and a Single 280mm disc in the rear. The front suspension was a Ceriani telescopic forks while the rear was equipped with a Swinging fork, Ceriani adjustable shocks. The 750SF2 was fitted with a 19 Liters / 5.0 US gal fuel tank. The bike weighed just 215 kg / 474 lbs. The wheelbase was 1452 mm / 57.2 in long.

Photos[edit | edit source]

Laverda 750SF2 Laverda 750SF2 Laverda 750SF2

Overview[edit | edit source]

Laverda 750SF2









SF2 (1974)

The most noticeable modification was the adoption of a 280mm Brembo disc front brake. This was replaced by dual discs of the same size almost straight away, so only a handful of bikes came with a single unit. Also, most machines were sold with a dual, rather than the previous solo saddle. Other smaller changes concerned items such as the headlamp and the tail-lamp. The drum rear brake and wire wheels were retained, as were the Nippon-Denso instruments.






Road Test 1975

To students of modern motor cycle design, there is very little in the specification of the Laverda 750SF twin to get excited about. By contemporary standards, the machine is positively archaic and should have been pensioned off years ago. Its engine is a 744 cc parallel twin with a single-overhead camshaft and drive to the rear wheel is by a triplex primary chain, five-speed gearbox and a simple rear chain. The bike is heavy and until a rider is familiar with it, apparently very awkWard to ride. On the other hand, such an analysis ignores many of the reasons for the existence of superbikes. For the Laverda 750SF is one of the most aggressively attractive motor cycles to appear from Italy and to many eyes still puts the bigger 981 cc three-cylinder Laverda into the shade on looks alone. The engine, originally conceived in the late 1960s as a 650 cc unit, was unashamedly based on the very popular 250 cc Honda CB72 twin with sharply-angled cylinder finning running to the top of the cambox. The whole line of the machine suggests speed - the tank is long and classically-styled and the rear seat can be an optional racing-style unit with a sleek back, while by very subtle positioning of the handlebars, footrests and running gear, the whole picture is of a machine made for fast and aggressive riding: The 750SF did not always look that way. As originally designed it looked strangely cumbersome and it was not until 1972 that it gained the looks that have kept it a favourite despite the many more exotic machines that have come onto the market in the meantime. In appearance, the latest versions of the SF are well up to date, with cast-alloy five-spoke wheels and potent disc brakes, two on the front wheel and one on the back. Laverda were the first to adopt the excellent Nippon Seikki instruments from Japan in favor of the poor Italian examples and still use them, the current versions being identical to those found on the bigger Hondas. Switchgear is also from Japan and is the same as that found on Suzukis. The performance of the SF however, shows the limits of the engine. Once one of the fastest and most powerful 750 cc machines, the SF is now merely average with a top speed of 118 mph and a standing quarter-mile time of 13-8 sec, figures that can be equalled or bettered by the quicker 550 cc machines. But the 750SF has many other virtues which were shown up when testing the 1975 model (identical to the latest example except for the wheels and brakes). New in 1975 were the twin front discs, replacing a massive four-leading-shoe drum brake, and a more powerful German Bosch quartz-halogen headlamp. A year earlier, bigger Delorto carburettors with 32-mm chokes and accelerator pumps plus a higher lift camshaft, had given the 750SF a sportier nature. While much more lively in the upper rev ranges, the bike is still flexible enough to pull well at low revs. Most of the power is developed between 5,000 and 8,000 rpm, the rev limit, with a maximum of 65 bhp. The bike is just as happy to chuff along at a walking pace in bottom gear while idling at 1,000 rpm.


Despite the use of the accelerator pump carbs, fuel consumption has improved on the Laverda SF over the years, and the latest version benefits from leaner mixture settings. Overall the 750SF returned between 42 and 48 mpg, offering a total range of 180 miles. A drawback of the leaner carburation proved to be a reluctance to accept full throttle during acceleration tests, and which necessitated heavy slipping of the clutch instead of the usually more effective, and quicker getaways offered by spinning the rear wheel The 750SF is a picture of ruggedness, which in reality is not far off the truth. The engine is built to massive proportions with a four-roller-bearing crankshaft having wide big ends and running in thick castings. Bore and stroke are slightly oversquare at 80 mm by 74 mm and the chain-driven overhead camshaft runs in big roller bearings. Unusually on a modern bike the electrical system is supplied by a dynamo which is rubber vee-belt driven from the offside end of the crankshaft, as is the electric starter. The first acquaintance with the bike is hardly impressive either, particularly if you have to ride it in town. Out of its element on the fast and open road, the 750SF feels rough and gawky, and only really comes alive when driven hard and rushed through demanding bends. Then the message come through loud and clear, that it is a true sporting bike in the best tradition. At speeds below 25 mph the steering is heavy and there is some degree of 'understeer' that requires an application of pressure to the handlebar to maintain a line. But buzzing the engine to 7,500 rpm through the gearbox (with almost BMW-like clunks with ragged changes, or crisp ones clutchless), exhaust booming out its deep note, the 750SF smooths out well for a vertical twin, and the steering becomes progressively more taut, just like a racing bike. A reason for the smoothness compared to other vertical twins is the total mass of engine and the spine-type frame, made of thick wall tubing and gusseting. By common standards the frame is very substantial and produces rewards both in longevity and giving a feeling of being glued to the road. With a weight of over 500 lb it is a credit to Laverda that the 750SF performs as it does. Set up for fast road work and most comfortable when breezing along at a 90 mph gait, the drape-over-the-tank rider's stance makes slow riding a chore. The footrests are adjustable, as on the 981 cc three, giving a fair range and making up for the tall seat height. Two seats are available, the racing type with a toolbox in the rear, giving just about enough room for two or a more mundane-looking dual seat. With the aid of perfectly-matched suspension, the bike sails securely through corners without deviating from its path. Spring rates are hard but to be expected on this sort of machine. The tires spoil the handling when the machine is cranked near the limit. Metzelers may be fine on a BMW but they are hardly suited to the Laverda. Dunlop TTlOOs as were fitted to earlier SFs and, we are told, are now the standard equipment, give much better grip on the side-walls. Although the engine is passably quite mechanically, the triplex-chain primary drive produced some chatter under power and the clutch, while normally smooth and quiet, replied to the standing start tests by grating on the take up and subsequently slipping at speed. Augmenting the handling well, the brakes are fabulous, despite the all-up weight of the Laverda. Drawback is that the dual discs increase the unsprung weight over the old drum unit. Electrically, the bike was faultless, but we were surprised that Laverda have retained the small and archaic CEV rear lamp while replacing the headlamp with the brilliant Bosch quartz-halogen unit. No praise can be great enough for the fabulous air horns. Instruments and switch-gear are good in quality and convenience. Varied and well finished, the toolkit is easily found by unscrewing one of the sidepanels, and proved sufficient for most of the usual tasks. Apart from poorly completed chrome-work - nickel was showing through on the silencers - the general finish of the bike is good. The only real snags we feel were a neutral lamp that flickered on regardlessly towards the end of the test, and buckled rear wheel adjuster, legacy of an attempt to break traction in the acceleration tests. If you are turned on by the Italian looks and aura and want a solid and reliable machine - a man's bike as they would have said once - then the SF is the only machine for you.

Road Test 1975

Make Model Laverda 750SF2
Year 1974 - 75
Engine Type Four stroke, parallel twin cylinders, SOHC, 2 valve per cylinder
Displacement 744 cc / 45.4 cu-in
Bore X Stroke 80 x 74 mm
Cooling System Air cooled
Compression 8.9:1
Induction 2x 36mm Dell'Orto PHF carburetors
Ignition Bosch electronic
Starting Electric
Max Power 65 hp / 47.4 kW @ 7300 rpm
Clutch wet plate
Transmission 5 Speed
Final Drive Chain
Front Suspension Ceriani telescopic forks
Rear Suspension Swinging fork, Ceriani adjustable shocks
Front Brakes 2x 280mm discs
Rear Brakes Single 280mm disc
Front Tire 3.50-18
Rear Tire 4.0-18
Rake 28.0°
Trail 82 mm / 3.2 in
Wheelbase 1452 mm / 57.2 in
Seat Height 790 mm / 31.1 in
Dry Weight 215 kg / 474 lbs
Fuel Capacity 19 Liters / 5.0 US gal