Magni-BMW MB2: A marriage of convenience and a better BMW

Bike Profile

1982 Magni-BMW MB2.

Story: Jim Scaysbrook • Photos: Sue Scaysbrook and Alan Cathcart archives. 

Arturo Magni – A proud innings

Only weeks after celebrating his 90th birthday in 2015, Artuo Magni passed away at his home north of Milan. To generations of fans, Magni was the genius behind the perennial success of the MV Agusta works team, and a guiding influence to generations of MV riders including Surtees, Hailwood, Hocking and Agostini. But his Grand Prix CV predated the MV team, stretching as far back as the days when the Gilera four cylinder racers, designed by Pietro Remor, ruled the roost. His association with Gilera is not surprising, given that he was born in the factory’s home town of Arcore, virtually next door to the famous Monza Autodromo. As a lad, however, Arturo’s chief interest was model aircraft, which he designed and constructed himself. Inevitably, this led to similar exploits in the field of full-sized gliders, which he flew himself with considerable success. One of his gliding mates was Ferrucio Gilera, son of the Gilera boss Giuseppe, and after the war, he accepted a position with the factory to assist in the development of the new 4-cylinder GP racer which dominated the 500cc class for eight seasons. 

Arturo Magni (here with Giacomo Agostini) was head of the MV Agusta race team until 1976.

In 1950, Count Agusta managed to lure Remor away from Gilera to design the first MV-4, and Magni went with him. In 1959, Magni became the head of the MV race department and remained there until the team pulled out of racing in 1976, during which time 270 GP victories were taken, along with 75 world championships. Magni had sole control of the race team which included the development of the three, four and six cylinder machines. With MV’s withdrawal, Magni decided to strike out on his own, basing his new operation at Samarate. Here he was joined by his two sons, Carlo and Giovanni. The new operation was called Elaborazioni Preparazione Magni (EPM) and initially concentrated on making after-market performance parts for the MV Agusta 750 street bikes, such as chain drive conversions for the shaft-drive models and engine kits to raise the capacity from 750cc to 861cc. The fledgling company also produced its own cast alloy wheels, a section of the business that became highly successful under Carlo’s management. 

Magni BMW on display at the 1983 Milan Show.

A major addition to the line of MV components was an all-new frame, introduced in 1977, which became the basis for the new 750 MV Agusta Sport, but this contract lasted only until 1980 when MV production ceased. Magni was forced to look elsewhere for engines, initially building a run of 300 Honda 900 models, followed by 150 BMW flat twins. But with BMW concentrating on their new four-cylinder model, Magni had trouble sourcing a reliable supply of the twins and decided instead to concentrate on a new venture with Moto Guzzi, the result being the Le Mans with the Guzzi engine in a Magni frame with a parallelogram swinging arm which became the company’s signature. The Magni chassis, and especially the swinging arm, transformed the handling of the Guzzi by overcoming the torque problems created by the shaft drive, and the model sold well, with over 900 produced. An eight-valve model followed – the Moto Guzzi Magni Australia – but once again, the supply of engines dried up and Magni turned to Suzuki to use the 1200cc Bandit engine. 

Moto Magni is still run by Giovanni Magni, and currently produces a range of four motorcycles.

The show must go on. Giovanni Magni with Magni-BMW and Magni MV-3 800 Filorossa in 2016.

The MB2

The BMW R100 powered Magnis came in two forms – the naked MB1, and the MB2 with its full fairing and extra accoutrements. It is believed a total of 175 were built, of which around 100 were MB2 models. The MB2’s strongest suit is not its specification, but its rarity. This machine is number 3 of the 100 built and somehow found its way to Japan, from where it was recently imported by Sydney classic specialists Old Gold Motorcycles of Londonderry. A notable feature of the frame, which differs from other Magnis, is that it actually bolts together to permit easy installation and removal of the engine/transmission unit. The frame itself is made from chrome-moly tubing, argon-arc welded, and Teflon-coated ball bearings house the swinging arm pivot. The result is a much stiffer frame than the original BMW, with a weight saving of two kilograms. However the significant improvement in handling is more due to the weight distribution, with the engine placed further forward and wheelbase extended by 30mm to 1490mm. All this affects the way the power is transmitted through the cardan shaft, under both acceleration and braking. 

This machine is number 3 of the 100 built and somehow found its way to Japan, from where it was imported by Sydney classic specialists Old Gold Motorcycles of Londonderry.
The Magni frame for the BMW.
BMW instruments are mounted on a very flexible bracket.
Left: Engine is fed by 40mm Bing carbs with accelerator pumps. Right: Each cylinder head has twin spark plugs.
Rear brake pedal operates slave cylinder. Note the box section swinging arm.
Left: Forcelle Italia front forks carry EPM wheel with Magni’s own disc rotors and Brembo calipers. Right: Underslung rear brake caliper on Magni disc.
Rear suspension is by Marzocchi piggy-back reservoir shocks.

Originally, both the MB1 and MB2 were offered in kit form without engines, but demand for complete machines led to production of ready-to-ride models, with R 100/7 or R 100 RS engines. A complete Magni MB2 scaled in at 25 less than a BMW R 100 RS.

On the road

To me, old BMW boxers always feel…loose. Everything wobbles a bit – not a lot – but enough to let you know it has a pulse, a living, throbbing pulse. The engine pootles around beneath you, seemingly tapping its metaphoric foot in time to a time-honoured cadence. Control levers jiggle happily, keeping their own time. Even the instrument panel, in this case, has a bit of a shimmy going as it nestles beneath the windscreen. Once under way, this looseness permeates every aspect of the ride, which is not to say it is unpleasant, just…loose. However the Magni definitely has a different character to a conventional R100, from which this mill is plucked. It actually steers very well, and for a fully-faired motorcycle, has an excellent turning lock. The 35 year-old front brakes feel their age, in that not much happens until a substantial amount of lever pressure is applied. Then they do actually work well, hauling the Magni down quite rapidly. The rear brake is a floating disc with the caliper suspended below. The tyres are 35 year old as well, so no crash stops, nor spirited cornering was attempted. 

“I suspect the complete chassis package is considerably lighter than the BMW, and it certainly feels it.” – Jim Scaysbrook

The switch gear, also ex-BMW, is typically complex, a BM trait until fairly recently. The turn indicator lever is hidden away at the base of the left switch and difficult to actuate, but once you figure out what does what it becomes less of a problem. What is a problem, is keeping track of what’s going on via the twin BMW instruments, which are mounted on a flimsy L-bracket secured to the facia by a multitude of 6mm bolts. I can’t believe this could be a Magni fitting, yet, closely studying period photographs, I am inclined to believe it is. The combination of the light transmitted through the heavily tinted screen, and the aforementioned proclivity for the instrument cluster to perform its own version of the Hippy Hippy Shake, means information such as speed and engine revolutions is only conveyed in the vaguest of manner. The ignition switch also takes some finding. You’ll eventually located it up inside the fairing, poking out of the left side of the headlight shell. 

Anyway, enough nit picking, let’s ride. There’s plenty of urge from the flat twin, which breathes through oversized 40mm Bing accelerator pump carbs, and is fired by twin spark plugs on each cylinder head. It’s nothing major in terms of performance, but the increase in efficiency also translates to much improved fuel economy. There’s no complaints in the suspension department. Up front is a set of what were originally Ceriani 38 mm forks, state of the art in their day, which were reproduced for Magni by Forcelle Italia and later morphed into Paioli, do their job well and have quite long travel, much of which is used up under braking. The forks have five positions for damping adjustment. At the rear in this machine sit a pair of Marzocchi ‘piggy-back’ reservoir shocks, which I have not seen in any of the period photos, but are probably a later addition. In any case, they work fine, and look rather snazzy too. Naturally, the Magni runs a pair of the company’s own cast-alloy six-spoke EPM wheels, the rear one housed at the end of the box section swinging arm. I suspect the complete chassis package is considerably lighter than the BMW, and it certainly feels it.

Specifications: 1982 Magni-BMW MB2

Engine: BMW R 100/7. Air-cooled OHV opposed twin.
Bore x stroke: 94mm x 70.6mm
Capacity: 980cc
Carbs: 2 x Bing 40mm.
Transmission: 5-speed, single plate clutch with shaft final drive.
Chassis: Double cradle tubular chrome-molybdenum steel frame with demountable beams.
Suspension: Forcelle Italia 38mm front fork, twin Marzocchi rear units.
Brakes: Front: 2 x Brembo single piston callipers on 230mm Magni iron discs.
Rear: 1 x Brembo single piston calliper on Magni steel disc.
Weight: (Dry) 190kg.
Fuel capacity: 26 litres.
Power: 81 hp.

This article first appeared in Old Bike Australasia Issue 67.