The Ducati Monster Bible

Introduction

When we think of Ducati, it is the company’s racing and sporting success that immediately springs to mind. And while its reputation for production bikes was built and sustained by a series of race replica motorcycles, these were not always the most successful in the marketplace.

The Monster’s creation in 1992 arose through expediency. At the time, Ducati was barely profitable. Its success in World Superbike racing had only just begun, and Ducatis were still considered eccentric motorcycles for the cognoscenti. Most developmental resources were being utilised by Massimo Tamburini at the Cagiva Research Centre in San Marino, in the design of the 916. Ducati was also a considerably lower volume manufacturer than today, producing a total of 4063 motorcycles in 1990, 8061 in 1991, and increasing to 12,049 in 1992. Ducati’s owner at the time, Cagiva, wanted to increase production (and hence profitability), but the new 916 was always going to be an expensive production proposition. The Ducati Supersport range was struggling, and the sport touring Paso never really succeeded. Cagiva needed a new product that would not only expand the company’s customer base, but was also profitable.

As it was very much an amalgam of existing components, the Monster was the perfect answer to Cagiva’s conundrum of how to increase production with the minimum of investment outlay. It was also a gamble, but it paid off. By 1995, 20,989 Ducatis were rolling off the Borgo Panigale production line, most of them Monsters. When TPG bought Ducati in 1996, again it was the Monster that sustained the company, with production soaring to nearly 40,000 in 2000. Ducatis were no longer only idiosyncratic motorcycles for the connoisseur. They had become mainstream motorcycles, and the Monster was largely responsible for this change in status.

So while Ducati is remembered for years of World Superbike domination and recent MotoGP success, its most enduring production model has been the Monster. This book attempts to unravel the myriad of different Monster models that have been produced since 1993. The emphasis is on the technical development, and how the Monster has evolved. This is not a workshop manual or a guide to the pitfalls of ownership, and neither is it a guide to modification or customisation – there are other books that deal with this. But the Monster remains one of the most practical and useable of all Ducatis, and every variant is described in detail.

Ian Falloon

The first Monsters: 900, 750 and 600 1993-1999

Ducati’s history has been one of ups and downs, and while the era under Cagiva ownership was characterised by periods of financial insecurity, it also resulted in landmark models that ensured the company’s survival. Cagiva provided the impetus for the birth of the Desmoquattro twin, initiating an unmatched ascendancy in World Superbike racing. It also engaged Massimo Tamburini, arguably the greatest contemporary motorcycle designer, to create the 916, a milestone machine in terms of both function and design. But the one model that ensured the company’s survival was the Monster, or ‘Il Mostro.’ Although the Monster was a parts bin special compared with the 916, it created a niche market that would see it become Ducati’s most popular model. Now, nearly two decades on, and with more than 250,000 produced, the Monster is the only remaining survivor of Ducati’s range from the 1990s.

First displayed at the Cologne Show in October 1992, the M900, nicknamed ‘Il Mostro,’ was the product of Varese-based Argentinean designer Miguel Angel Galluzzi. Galluzzi was born in the USA and studied at the Pasadena Design Center in California. The term ‘monster’ was derived from the Latin word ‘monstrum,’ referring to a divine sign, a prodigy, or something exceptional. Originally a monster was the sudden emergence of something extraordinary that violates nature and acts as an omen and warning to mankind. This omen brought about a sense of wonder and amazement, and led to the term being widely used in music, fashion, and art. From the legends of the Loch Ness Monster and the Abominable Snowman, to the monsters in movies like The Adams Family, Fritz Lang’s Metropolis, King Kong, Dr Jekyll and Mr Hyde, Frankenstein, and Browning’s 1932 masterpiece Freaks, the monster became the protagonist.

In 1991, Galluzzi built a stripped down naked version of a Ducati 888 Superbike. Originally created for himself, when Claudio Castiglioni saw Galluzzi riding it to work he immediately ordered him to get it production ready. According to Claudio Castiglioni in a recent interview with the author, I really liked the elemental look, and thought it would be a wonderful companion to our Elefant, a bike I still have fond memories of. Right until the last minute it was intended to launch the bike as a Cagiva, alongside the Elefant trail bike, but pressure from Ducati’s manager, Massimo Bordi, saw the Monster become a Ducati. After nearly a decade outside the motorcycle industry Bordi is now back with Cagiva in Varese, and recently said to the author, As many of the components, such as the engines, were built at Borgo Panigale in Bologna, it made sense to build the Monster in Bologna and call it a Ducati. Galluzzi originally wanted to use the 888 engine in the Monster, but at the time the 900 Supersport wasn’t selling well, and there was a surplus of air-cooled 900 Desmodue engines. There was also a problem with the size of the battery needed to power the fuel-injection on the 888, and a large battery simply couldn’t be packaged effectively. Out of a combination of existing components Galluzzi cleverly created a naked and minimalist street bike, with all the eminent sporting credentials expected of a Ducati. As Galluzzi said of his impetus for creating the Monster, What does a motorcyclist need to have fun? All the bike needs is handlebars, an engine, two wheels, and a tank to fill with petrol. The road does the rest ...

Claudio Castiglioni (left) and Massimo Bordi were instrumental in seeing the Monster evolve from Galluzzi’s personal prototype into a production motorcycle.

1993 model year

Monster 900

Although it was originally intended for the 1993 model year, 900 Monster production was delayed until May 1993 because of component supply problems. The early 1990s were particularly problematic for Ducati and Cagiva, with production constantly interrupted through difficulties in the supply of various components. By the time the Monster entered production it was almost a 1994 model year bike, and the only model initially produced was the 900.

The first Monster 900 was a hybrid model, but established a style that continues nearly 20 years on.

Engine

The Monster’s 904cc engine was shared with the 900 Supersport, with the same engine number sequence. This engine was the new 6-speed large crankcase design first seen in the 1989 water-cooled 906, and soon afterwards with the air/oil-cooled 900 Supersport. The crankcases, primary drive and gearbox were initially shared with the 851 and 888, and in every respect were stronger than those of the smaller crankcase 5-speed 750. This was particularly evident around the cylinder base, where the contact area was increased to give a more stable base to the cylinders. Larger ball bearings were fitted to both primary and secondary shafts in the gearbox, and the clutch side bearing was increased to 62mm (from 52mm). The gearbox shafts were relocated on the crankcase for a greater centre-to-centre clearance, and fewer lower-end parts were now interchangeable with the smaller engines. The gears of the 6-speed gearbox were now wider to handle the increase in capacity, and to reduce the torque and speed up the clutch there was also a new set of straight-cut primary drive gears with a ratio of 2:1 (62/31). This seemed a strange choice of ratio as there was no hunting tooth to spread the load, and the gears sometimes broke, but it would be used for the next ten years in the large crankcase engines. Another development with the larger engine was the new timing belt covers that allowed for adjustment and checking of belt tension without removal of the complete cover. The belts and pulleys were also stronger, now with round rather than square teeth, and included a revised tensioner.

Unlike the 900 Supersport, the M900 oil cooler was positioned above the front cylinder.

The cylinder head design was considerably updated for the 900’s 92mm Asso pistons. Not only were the valves larger (43mm inlet and 38mm exhaust), but there were also new camshafts with higher valve lift (11.76mm inlet and 10.56mm exhaust). The valve timing was unchanged from the 750, but the camshafts had steeper ramps. Although the valves were still inclined at 60 degrees, the combustion chamber was a new ‘tri-spherical’ design, the cylinder heads now machined in three stages by centering milling machines first in each valve guide, followed by the sparkplug seat. The result was a more consistently shaped combustion chamber, the ridges formed at the intersection of the three machining operations ensuring a reasonable compression ratio, even with flat-topped pistons. Turbulence was also increased through the large squish band, historically a typical Ducati feature that contributed to excellent fuel consumption and combustion. The flat-topped three-ringed 92mm pistons were also ‘H’ section, but used a 19mm gudgeon pin (up from 18mm on the 750, while the similar 92mm 851 piston featured a 20mm gudgeon pin) and provided only 9.2:1 compression. The top piston ring was L-shaped, and as with the 851 and 888 the piston crowns were cooled with oil sprayed from nozzles underneath. The lower end was also stronger, with the big-end bearing size increased to 42mm (from the 40mm on the 750), although the main bearing shafts were still 35mm. With an extra 6.5mm of stroke over the 750, conrod length grew from 124mm to 130mm, providing a length to stroke ratio of 1.91:1. The cooling system was a development of the air-oil system of the 1989 750 Sport, the larger engine now including oil passages between the bore and outer cylinder wall. This circulating oil drained via two external lines on the left side of the cylinders. An external radiator cooled the oil, and while this was located below the front cylinder on the Supersport, on the Monster the oil cooler was much more sensibly positioned above the front cylinder.

By the time the 900 engine appeared in the Monster in 1993, it had already undergone considerable development. As the crankcases were designed for the high-performance Desmoquattro series, they were more than adequate for the modest power of the two-valve air-cooled engine. But problems with cracking on the Desmoquattro saw the crankcases receive strengthening around the base of the cylinder for 1991. Instead of painted black, the crankcases were now unpainted aluminium, but they retained the black cylinders and heads. The engine covers were also black, but with silver rocker and clutch covers, and the clutch actuation was moved to the left side.

Powering the M900 was the air-cooled twin from the 900 Supersport.

The most significant new feature for 1991 was the dry clutch. The first of several modifications, this clutch was superseded in early 1992, but was so problematic that the clutch friction material was modified three times during 1991. From 1992 a 2mm steel plate splined to the clutch drum replaced the 3.5mm plate splined to the clutch housing. The complete 16-plate set consisted of two 2mm driven plates, one 3mm driving plate, one 1.5mm convex spring plate, and six driving plates alternated with six driven plates. Finally, after several years of clutch experimentation on 900 engines, this clutch set would stay, continuing until the advent of the fuel-injected model in 1998. The flywheel to flange fastening was also improved, with seven (rather than five) screws, these also stronger. During 1991 the valve guide seals were changed to Viton from silicon rubber, and from January 1992 the valve guides were changed from cast iron to aluminium-bronze. Cylinder heads featuring these new valve guides were identified by a ‘V1’ marking on the timing cover side.

For 1992 the 904cc air/oil-cooled engine received a larger, 350-watt alternator (up from 300 watts), and a new oil pressure switch. An important