Saturday 25 June 2011

Laverda SF750 Topspeed Bikes

Laverda SF750
Laverda SF750
Laverda SF750
Laverda SF750Laverda SF750

Thinking of buying a 750 Laverda twin? Dave Minton rings the changes between the models and offers shoppers well-proven advice...

In the first installment, Laverda introduced their 750 twin parallel twin and - against the odds - it proved to be one of the best. They could hardly keep up with customer demand it first, but by 1972 the competition was a lot hotter and it came with four cylinders.
1973 SF1. Also available in colour.

So for 1973 Laverda's 750 twin got the boost it needed, in the shape of the SF1. By this time sound level regulations were intruding so Laverda was faced with the conflicting difficulties of increasing gas flow and decreasing exhaust noise. Laverda achieved both ends with large diameter exhaust pipes (1.6-inch) interconnected by a transverse collector box, new style Dell Orto 36mm pumper carbs and a matching new camshaft. These mods lifted power to a claimed 66bhp at 7300rpm, and top speed rose accordingly to around 117mph.

The bike from particular year is generally regarded by afficianados as the quickest of the SFs. While their handling was heavy, although quite typical of the period, not much else cornered more sure-footedly than an SF.

Despite the apparently modest power increase, the SF1s were noticeably faster on nip-and-tuck riding. In the first place they were fitted with a single Brembo 11-inch disc front brake which, while no more powerful than the old drum, could be used repeatedly without fading. And in the second place, SF1 acceleration in normal highway use was undeniably superior to SF, thanks to a further lightened flywheel.

But the whacking great collector box beneath the bike was the problem, as any SF1 owner worth his salt soon discovered when riding through a series of bends. The thing grounded with all the eagerness of a pig after truffles, although with an appallingly amplified volume of squeal. Exhaust apart, you will also recognise this model by its squat little chromed CEV headlamp and bat-wing Lucas switchgear.

Then in 1974 came the SF2 where the SF engine reached the pinnacle of its road-going development, although not until ungagged did it breathe freely enough to realise its full potential, when with matching recarburation 120mph was available. Along with new Ceriani teles, Laverda doubled up on the front brake discs and replaced the rear drum with a single disc. Thankfully it exchanged the abominably manufactured Lucas switchgear for Nippon Denso's Suzuki pattern. Another worthwhile change was to a black Bosch headlamp. However, like many low-volume production-run models, single items may migrate from one model year to the next, often as a result of the original purchaser's personal specification. Thus the best way to date any bike is from its engine number rather than by its headlamp or braking equipment.

The SFs achieved their final form in the shape of the SF3 which arrived in 1976. The most obvious change was to the wheels which lost their wire spokes in favour of cast aluminium ones, although they remained suited to tubed tyres only. A lockable, hinged dual seat with a duck-tail box behind finished the revisions.

Laverda Jota Fast Bikes

Laverda Jota
Laverda Jota
Laverda Jota

Laverda Jota
Laverda JotaLaverda Jota v Kawasaki Z900

It's 1976 (don't argue!). You want to buy a motorcycle. A Very Fast motorcycle. It must come with a warranty and be reliable, so thinly-disguised racetrack refugees are out. What to buy?

Honda is still churning out basically the same CB750 as they did in 1969. The GoldWing isn't really terribly fast and handles like a hippopotamus in a supermarket trolley. Suzuki's best effort is the GT750 Kettle. Until the new XS750 triple reaches the shops Yamaha can only offer a 650cc vertical twin - and if you wanted one of those you'd get a Triumph or a Norton, even if you suspect that the whole British industry is about to go belly-up.

The Moto Guzzi Le Mans 850 looks great and can clock over 130mph, but it's just another twin. And it has shaft drive, which everyone knows makes the gearbox awful and ruins the handling. Same goes for the BMW R90S, which you might consider buying when you're old and grey, perhaps. A motorcycle with a clock? Whatever next?

No; perusing the bike mags reveals that if speed is your need it really has to be a Kawasaki 900 or a Laverda 1000. The Kaw' has been around since 1973, running through Z1, Z1A and Z1B variants before turning into the Z900 for '76. When launched, the big 903cc four engine was the absolute King, its 82bhp being enough for a 12.3 second standing quarter mile and a top speed of 132mph. At the other extreme, it could dawdle along at just over tickover in top and still accelerate strongly, just by twisting the throttle. As usual for a Japanese bike, only the handling was slightly suspect. The frame seemed basically OK, but the forks looked weak, and those instant-slip nylon tyres were best replaced by a set of decent Dunlops or Avons as soon as possible. Mind you, with so much power on tap, after a couple of thousand miles the rear boot will be vaporised, anyway. That's another twenty-five quid down the drain, on top of £1369 for the bike - which is enough to buy a nice car, as boring people keep pointing out. Still, unlike a Cortina, at least a Z1 does 45mpg, which is a real bonus now that a gallon of 2-star is an extortionate 70p. That's fourteen bob in real money, remember!