DUCATI PANTAH / F1
Article #10, 12 April 2011 by Harné Heuvelman
In 1979 Fabio Taglioni once again proved to be a genius with the development of the Ducati Pantah. Already in 1973 he had envisioned the use of toothed rubber belts for driving the camshafts, not usual at all in the seventies. Belt-driven camshafts would be cheaper to produce and would prove to make engines run a lot quieter. The advanced design of the Pantah engine has proven its importance over the years as Ducati’s of today still use the same basic principles.
Ducati wanted to expand the range with small displacement bikes. The single cylinder Desmo’s were discontinued as the technical layout was out-dated. The parallel twins (like the 350 GTL, 500 GTL and 350 Desmo and 500 Desmo) struggled for market acceptance throughout their lifetime. It was clear something new had to be developed and so Fabio Taglioni was assigned to base a new design on his 90 degree L-twin ideas.
The result was the Ducati 500 SL Pantah, introduced in 1979. The engine’s basic layout was copied from the earlier bevel drive twin with vertically split crankcases, a 90 degree angle, with the horizontal cylinder still inclined at an angle of 15 degrees. The design incorporated left side gearshift as a standard as well as a starter motor now located underneath the horizontal cylinder. The single overhead camshafts were driven by a toothed rubber belt and incorporated Ducati’s famous desmodromic valve actuation. The engine design was initially meant for a maximum displacement of 500cc but, as we’ll see later on, it grew larger and larger.
The frame also was a complete new development for the 500 SL; Ducati’s first trellis frame with two parallel tubes. This too set the standard for all Ducati’s to follow! It is easy to see the resemblance between the original Pantah frame and that of any modern Ducati.
The 1979 500 SL Pantah was fitted with Marzocchi suspension front and rear, Brembo brake system with dual front discs and aluminium FPS wheels. It received a ‘café racer’ style with a newly designed half fairing, clip-on handlebars and rear set foot pegs.
Not much changed over the course of 1980, but 1981 saw market introduction of the 600 SL. All basic specifications were the shared between the two models, apart from engine displacement. Both the 500 SL and 600 SL received a new top-half fairing and most of the 1981 models have Paioli rather than Marzocchi suspension. Very minor updates were introduced over the following years, with perhaps the most important being the cable operated clutch of the 1982 600 SL rather than the earlier hydraulic operated one.
Ducati had been struggling with the more ‘touring’ focussed bikes in their product range ever since the infamous 750 GT. Although this model was a great success and is even now considered one of the finest Ducati’s ever build, its successor, the 860 GT, was a complete styling failure. With the success of the SL Pantah, however, management decided to introduce a touring bike once again in 1982: the 600 TL. Sharing all specifications with its sporty brother, the design of the bike incorporated an unusually large fuel tank and an ugly top fairing. Reception was poor and production stopped already one year later.
A range of 350cc Pantahs: the 350 XL, 350 TL and 350 SL were introduced in 1982 specifically for the Italian market. Tax legislation made bikes under 350cc popular in Italy and the range of 600cc Pantahs was simply given a smaller engine while retaining most of the other specifications.
Where the 500 SL was discontinued for 1983, the 600 SL received a new colour scheme matching that of the Mike Hailwood Replica and an optional Conti ‘two-into-one’ exhaust.
As a true racing company, Ducati had a tradition for making small numbers of hand-build racers available for customers. This was done in 1982 with the 600cc TT2, based on the Pantah engine. With a highly tuned engine and a purpose designed Verlicchi frame, the TT2 and the later 750cc TT1 were among the best racers of their time and still are considered among the best racers ever build in Borgo Panigale.
Ducati needed to homologate some of the engine parts of the TT1 on a road bike and so the 650 SL was created in 1983. Although based on the 600 SL, the 650 SL received the longer stroke of the 750cc TT1. As it was only available in 1983, total production stopped at 288, making the 650 SL the rarest of all Pantahs.
The TT2 racing bike was very successful and in true Ducati style the racing bike would make its way to the road one way or the other. This strategy, previously employed on the 750 Super Sport and Mike Hailwood Replica proved to be a success and in 1985 the racer for the road was introduced: the 750 F1.
Although basically a 750cc version of the earlier Pantah engine, updates included new camshafts, straight cut primary gears, aluminium pulleys and black painted crankcase, cylinders and cylinder heads. The 750 F1 was fitted with a two-into-one Conti exhaust and the same carburetors as the 650 SL, but without air filters.
The frame however was based on that of the TT2 racer rather than on that of earlier Pantah models. It was designed so tight around the engine unit that no place was left to cover the belts on the left side of the engine. The fuel tank was aluminium and styled like the TT2 as well. The 750 F1 was fitted with Marzocchi front fork and a Marzocchi monoshock on the cantilever swing arm. Wheels were OSCAM with fully floating Brembo discs front and rear.
The 1986 750 F1 was updated in many ways. The crankcase was strengthened and formed the basis for the later limited production versions. The camshafts were updated and the con-rod strengthened. The cylinder heads were strengthened and received larger valves. The gear box got larger gears and the oil-cooling system was improved. For the first time on a Ducati road bike a dry clutch was fitted, later to become one the distinct Ducati features.
The 1986 750 F1 received a 40mm Forcelle Italia front fork but retained the floating Brembo discs at the front while the rear was now a solid type. The wheels were the same OSCAM’s but painted red instead of gold. The fuel tank now was made of steel instead of aluminium.
Ducati had been acquired by Cagiva in 1985 and although one can argue about the value the Castiglioni brothers added to Ducati, we won’t go into detail here. Fact is that the logo design changed in 1986 to match that of Cagiva, adding an elephant to the graphic design of the 750 F1.
In 1986 and 1987 a total of three limited edition 750 F1’s were introduced: the Montjuich, Laguna Seca and the Santamonica. As Ducati did before with the 1975 750 and 900 Super Sport; not much attention was given to road regulations…
The Montjuich (named after the Montjuich Park racing circuit in Barcelona, Spain) was the first to arrive and was uncompromising in every way. The engine was taken from the 750 F1 but with many changes: the crankshaft was different, the inlet ports were larger, the cams hotter, the carburetors larger and the gearbox altered. The dry clutch had an aluminium outer drum and ignition was Kokusan rather than Bosch. The Montjuich was fitted with an extremely loud Verlicchi 2-into-1 exhaust. It received an aluminium swing arm and Marvic/Akront wheels which had a polished aluminium outer ring (Akront) and a cast magnesium three-spoke centre (Marvic). Brakes were Brembo ‘Gold Series’ four-piston callipers with full floating discs. No indicator lights were fitted. Only 200 were ever produced.
With the next series: the Laguna Seca (named after the Laguna Seca race track in the USA), the concept was a bit softened. The exhaust was a lot quieter, there were indicators fitted along with a centre stand and the fuel tank was steel rather than aluminium. Wheels were now OSCAM aluminium but the ‘Gold Series’ Brembo brakes were the same as on the Montjuich. Although the Laguna Seca might have been a bit more ‘sensible’ than the Montjuich, it was still an uncompromised racer for the road. A total of 296 Laguna Seca models were produced.
The final special series 750 F1 was the Santamonica (named after the Autodromo Santamonica at Misano, Italy). It was basically a Laguna Seca with only minor changes: there was a dual seat fitted with removable cover and the Montjuich Marvic/Akront wheels were back. The Santamonica came with a new white and red colour scheme. A total of 204 Santamonica’s were ever produced.
Together, the three special series of the 750 F1 are among the most desirable Ducati’s of the 1980’s. The 750 F1 was discontinued in 1986 and replaced by the 750 Paso. The Pantah and F1 were the first Ducati’s with a belt driven camshaft and proved to form the basis of all Ducati’s to follow till today.
The Pantah and F1 engine’s basic layout was copied from the earlier bevel drive twin with vertically split crankcases, a 90 degree angle, with the horizontal cylinder inclined at an angle of 15 degrees. The design incorporated left side gearshift as a standard as well as a starter motor now located underneath the horizontal cylinder. The single overhead camshafts were driven by a toothed rubber belt and incorporated Ducati’s famous desmodromic valve actuation. The engine design was initially meant for a maximum displacement of 500cc but, grew up to 750cc over the course of its lifetime.
With the great success of the TT2 and TT1 racers came the 750 F1 which used the earlier Pantah engine as a basis, but included new camshafts, straight cut primary gears, aluminium pulleys and black painted crankcase, cylinders and cylinder heads. The three 750 F1 ‘Special Editions’ (the Montjuich, Laguna Seca and Santamonica) came with an engine taken from the 750 F1 but with many changes: the crankshaft was different, the inlet ports were larger, the cams hotter, the carburetors larger and the gearbox altered. The dry clutch had an aluminium outer drum and ignition was Kokusan rather than Bosch.
The Pantah came with Ducati’s first tubular trellis frame, later to become the standard for all models to follow. Early Pantahs were fitted with a 35mm Marzocchi front fork, later to be replaced by Paioli forks. The 750 F1 frame was derived from the TT2 and TT1 racers and had a monoshock rear swing arm. Only the 1985 750 F1 model had a Marzocchi front fork, later to be replaced by Forcella Italia forks, also on the three ‘special models’ (Montjuich, Laguna Seca and Santamonica).
References (recommended further reading)
Falloon, Ian (2004) ‘Standard Catalog of Ducati Motorcycles’, Iola: KP Books
Falloon, Ian (2000) ‘Ducati Belt-Drive Two-Valve Twins: Restoration and Modification’, Motorbooks International