Four stroke, 72° V-twin, OHV, 2
valves per cylinder.
Capacity
344 cc / 20.9 cu-in
Bore x Stroke
62 x 57 mm
Cooling System
Air cooled
Compression Ratio
11.0:1
Induction
2x 25mm Dell'Orto carburetors
Ignition
Electronic CDI
Starting
Kick
Max Power
39 hp / 28.5 kW @ 8500 rpm
Max Torque
33.6 Nm / 24.8 lb-ft @ 6300 rpm
Transmission
6 Speed
Final Drive
Chain
Frame
steel twin loop
Front Suspension
32mm Telehydraulic forks
Rear Suspension
Swinging arm dual adjustable shocks
Front Brakes
Drum
Rear Brakes
Drum
Front Tyre
3.25-18
Rear Tyre
4.10-18
Wet Weight
160.0 kg / 352.7 lbs
Fuel Capacity
14 Litres / 3.7 US gal
Consumption Average
51 mpg
Top Speed
97 mph
Among the rarest and most unusual
Italian bikes is Moto Morini's range of modular V-twins, produced in small
numbers from 1972 to 1993 at the family-owned Bologna works. The first to
appear was the 3½ (350cc), which was designed by Franco Lambertini and first
shown at the Milan show in November 1971.
It was followed in 1975 by a "bored and stroked" 500cc version which, although
it was much torquier, never achieved quite the cult following of the
charismatic 3½.
There are so few in South Africa that until recently I had only ever seen
three and I'd never ridden one so, when Lance Allam and Richard Piller offered
to lend me their neatly restored 1979 500 Sport, I grabbed the chance.
"Keep it as long as you like," they said, "Ride it around, use it as a
commuter – it's a nice street bike."
Lambertini's magnificent 72º V-twin is based on proven, conservative
engineering principles.
This was so different from the usual attitude of Italian bike owners that it
increased my curiosity even further – so I did exactly that and used this
24-year-old exotic rarity as daily transport for two weeks ... and I loved
every moment of it.
The cylinder heads are flat, the valves are parallel and the combustion
chambers are recessed into the top of the pistons. It's called a Heron head
and, if it sounds familiar, it's exactly the same as on a 1600cc Ford Kent
engine.
It also allows impressive compression ratios on ordinary petrol – the 500 runs
at 10:1, high for the period.
It's fed by two very ordinary 28mm Dell'Orto carbs mounted back-to-back in the
vee and drives via a (theoretically) dry clutch and a five-speed gearbox. In
typical late-1960s European fashion, the gearshift is on the right and the
kickstart on the left. An electric start is fitted, though that on the test
bike wasn't working.
The low centre of gravity allows the bike to flick from side to side like a
kitten chasing the wind.
No problem. The bike kickstarts easily although it takes about a dozen hefty
swings first thing in the morning. Hot, the bike bursts into life on the first
prod.
This idiosyncratic motor kicks out 31.3kW at 7500rpm with usable power from
2500 revs. It vibrates noticeably until just over four, at which point it
comes on song, smoothing out and surging strongly forward.
Morini's contemporary factory literature claims a top speed of 175km/h and the
Sport went easily up to 163 in performance testing, the little vee spinning at
6500rpm with no sign of distress, accompanied by a harsh and flat barking from
the replica factory tailpipes (no noise regulations in 1975, Cyril).
The clutch is firm and predictable, with a sudden take-up very close to the
grip, typical of multi-plate dry clutches. The test bike's clutch exhibited
some clutch drag when hot, due to a faulty seal having leaked some oil on to
the friction plates, but that's easily fixed with some solvent and steel wool
to remove the glazing.
As it was, it just meant I had to be careful to find neutral before the bike
stopped moving, not always as simple as it sounds because there's no neutral
light. The gear lever extends from behind the foot-peg and its action is a
little long but light and firmly positive.
After a little practice I was able to reel off seamless upshifts without the
clutch, although I always used it for downshifts out of respect to the box's
age.
conventional frame
This beautifully sculpted and surprisingly narrow motor is mounted in a neat,
conventional double-cradle frame welded from steel tubes with 35mm Marzocchi
cartridge forks in front and twin hydraulic shock absorbers, adjustable only
for preload, on the swing-arm.
The wheels are crisp cast alloy and the brakes are by Grimeca, twin 260mm
discs in front and a single rotor the same size on the back wheel, all with
opposed-piston calipers. This was cutting-edge stuff in the mid-1970s.
The rest of the bike is all borrowed: the switchgear and all the lights are
from Ducati's 860GT, the instruments from the Guzzi V50 and the fuel cap is
shared with every Laverda and Ducati of the period.
It has all proved durable and reliable and everything falls neatly to hand,
which is more than can be said for some modern machinery.
Weird features abound; the bike has a unique electronic fuel tap on the left
side of the tank which opens with an audible click when you switch on the
ignition – but the right (front) carburettor is fed by a normal three-position
manual tap just like any other bike of the period.
The motor has four breathers, all in a collector box behind the motor. To keep
the bike from dribbling all over itself, the twin overflow pipes are now led
into a 500ml bottle hidden behind the battery. In two weeks it collected about
a tablespoonful of oil.
Despite an odd riding position, with the footpegs rather too far forward for
the low, narrow clip-ons, the long, deeply padded seat is remarkably
comfortable with plenty of room to move around on longer rides.
Superb road-holding
The bike is a joyOn the road. The frame is taut and more than stiff enough to
cope with 31kW and a dry weight of just 160kg. The steering is razor-sharp and
as quick as a modern GP machine while the low centre of gravity and amazingly
narrow chassis allow the bike to be flicked from side to side like a kitten
chasing the wind.
On smooth roads the road-holding is superb even by modern standards, the
ground clearance more than adequate and suspension surprisingly supple. The
only time the damping shows its vintage is on bumpy back roads, where it
begins to patter when pushed.
The brakes take a firm squeeze to get them working but then haul the bike down
firmly and controllably – although the back brake is if anything a little too
powerful; I locked the rear wheel a couple of times at low speeds.
In heavy traffic the motor's quick response and mid-range torque let you grab
the narrowest of gaps and, unusually for an outright sports bike of any era,
it will sit at a red light for as long as you like, quietly idling at an even
1000rpm.
Within its limits, Morini's middleweight vee is a magnificently competent
package. On a twisty but well-surfaced road it's pure sex on wheels, yet it
will idle reliably and has the tightest turning circle I've yet measured on an
Italian bike.
It's as good a commuter as anything you can buy off the showroom floor, with a
healthy dose of vintage class. It's also widely regarded as the prettiest
motorcycle yetbuilt; certainly that air-cooled 72º V-twin is the most
exquisitely sculpted engine in motorcycling.
Allam and Piller were right; it's a very nice street bike. I didn't want to
give it back so thanks for the loan, gentlemen.
Source Dave Abrahams
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