Dennis Noyes Tribute

Eighties motorbikes tests

Ducati Pantah 500

Ducati Pantah 500

Here we have Dr Fabio Taglioni’s masterpiece, the Ducati Pantah 'half liter.' A bike that is capable of reaching speeds of 190 km/h (118 mph) with a light tail wind and maintaining an average speed of 185 km/h (115 mph) on tests going with and against the wind over the same track. Furthermore it can do this without any special preparation and with the mufflers and air filters limiting free intake.  The Pantah ranks first in the Spanish market in acceleration and maximum speed among all bikes of up to 650 cc.  Plus, despite its brilliant performance, at a constant speed of 120 km/h (74.6 mph) fuel consumption is barely more than 6 liters (1.585 gallons) per 100 km (62.1 miles).  However, the benefits and low consumption don't tell the half of it. The Pantah frame is more rigid than any we have seen on a motorcycle of its cylinder capacity, and the suspension and brakes are remarkably good as well.  The only major flaw of the Pantah is that it didn't come out three years earlier.

The current fashion for multi-valves with transverse engines has given V-Twins a somewhat dated image in recent years. Yamaha has already seen the advantages of this configuration, as well as Hesketh.  What a tragedy it would have been if inside of Ducati they had listened to those engineers who wanted to abandon the Taglioni design in order to jump right into the field of transverse engines of both two and four cylinders.

Because despite a stunning profile and an impressive pickup, the large displacement of high performance four cylinder engines limits the angle of inclination, increases the weight, raises the center of gravity and spoils the aerodynamics of the motorcycle.

We must remember that the two-cylinder V-Twin of the 1950s reached impressive speeds without revving the engine at high r.p.m.s and without exaggerated horse-power. At the beginning of the 1950s, for example, the legendary and flamboyant American, Rollie Free, dressed in a bathing suit (because the American Federation prohibited him from doing it naked) and wearing a cardboard helmet (because the same Federation required the use of helmets but didn’t specify what material they were made of) beat the world record for top speed with a quintessentially English Vincent Lightening two-cylinder V-Twin in 47 degree heat (116 degrees F)...managing to become the first man to break the barrier of 240 km/h. (149 mph) with a motorcycle fueled by carburetors. He did it without fairing, and without any significant changes other than unmuffled exhaust, carburetors without filters and the removal of the front brake. With an authentic 65 hp at 6,500 r.p.m., a narrow two-cylinder V-Twin can match the much more powerful four-cylinder tranverse engine. That is why, the Brough Superior, the Indian, Harley-Davidson, Clement V-4 and the Vincent, among many others, owe their fame and popularity to an engine configuration that permitted them to harness their maximum power.

What’s more, the Pantah, following in the footsteps of the 900 SS of the 1970’s and the Vincent Black Shadow (cantilever) of the 1950’s, is demonstrating that the laws of physics have not been altered.  The two-cylinder or four cylinder V-Twin placed lengthwise in the chassis, represents the best balance between its narrowness, aerodynamic penetration and low center of gravity.

To see the realities on the series bikes you have to rely on the real data and roundtrip average speeds on the same track with bikes that haven’t been specially prepared.  Using the figures obtained from the official MIRA circuit of the British Transport Ministry, and those published in Motor Cycle Weekly from London we see that in 1961 a Velocette 500 single cylinder reached 170 km/h (105 mph), while in the same year a Norton 500 Dominator two-cylinder reached 176 km / h (109 mph). These figures are more or less in line with the vast majority of the current 500s.   Plus, until the arrival of the Honda CX 500, the Kawasaki KZ 500, and the Laverda Montjuic, no 'half liter' series had ever been able to beat the record for the Daytona 500 Triumph, whose 178.6 km/h (111 mph) average was established in MIRA 14 long years ago.
Also, of these three, only the Laverda Montjuic with a weight of about 175 kg. (386 lb.) and a relatively low center of gravity, can be considered a bike suitable for serious sport riding since the Honda is high and fat and the Kawasaki wide.  As a result they have a very ineffective an aerodynamic penetration.

However, the Pantah 500, which was designed and then fine tuned for four long years by Dr. Fabio Taglioni in the Department of Prototypes of the Ducati Meccanica in Borgo Panigale, Italy, is simply the ideal sport 500, and for sport riding, the Pantah only has one serious rival amongst the other "four stroke bikes” of the world market... the Laverda 500 Montjuic with a two cylinder transverse engine. To see which of the two is more effective on the track, under regulations that allow very little preparation, we will have to look at Motorcycling Series Formula 2 races, but up to now in the Italian (Maximum Speed) and Spanish (Endurance) Formula 2 Championships the official Pantah 582 cc has kept its only important rival in line, the Laverda with a two cylinder motor with four valves in each one.  A feat that is not bad for a motorcycle that just hit the market.  The Pantah was born strong. 

In all I tried out three bikes, compiling only 746 kilometers of riding all together, but the high milage in the shakedown run is due to the necessity to personally break in each bike completely in order to get performances that are real and worthy of being comparing with motorcycles that were tested under almost identical circumstances and itineraries.

The first Pantah that I used was loaned to me by a British importer, but this was only to get a first feel, because (like the bike of Ferrero-Carrero loaned to Andrés Ruiz for the test) it hadn’t been broken in completely.  The second Pantah, loaned by Pep Giralt International Motos of Badalona, was used only for dynamic tests.  It was a bike with 5,000 miles on it and it had been broken in properly.  The third bike was loaned to me by Ricardo Fargas, but it was a 582 cc, and it was still being broken in after the transformation.

Through third parties, Andreu Virgili, director of Ducati, let me know that he wasn’t willing to let me use a factory model of the Pantah, as is usual for the MOTOCICLISMO shakedown test, because he didn’t agree with the tone and wording of the 10,000 kilometer Super Test of the Ducati 500 published in edition 656 of our magazine.  Given that the many distributors, agents, mechanics, owners and even some of staff of the Mototrans factory itself, told me that our test seemed fair and impartial to them, I still don’t think that Mototrans was trying to “punish” me for a conscientiously written review and a shakedown test, followed by a total dismantling of the motor with wear analysis done by an authorized repair firm.

The Pantah of this shakedown test is so extraordinarily good that it might seem to others that the test was rigged in order to not get on the bad side of Mototrans.  However, I believe that as readers, you will know that I never let anything color my opinion when it comes to analyzing bikes.

 

RABIDLY SPORTY

When I got to the foot of Montseny (the dinometric green bench that never lies) I knew that I was going to have an unforgetable day.  It was one of those cool and clear autumn days with a deep blue sky with a few little, scattered white clouds headed south.

I was accompanied by a friend on a powerful multi valve 900 cc, and from the first curves I saw that the multi valve couldn’t escape more than a meter from the Pantah.  While I saw sparks and heard the multi-valve scraping its bottom on the ground, the Pantah was so easy to handle on the curves that the slight advantage of the other bike in acceleration was cancelled out each time I turned or braked.

Later when I decided to pick up the pace (with the stopwatch now attached to the handlebar) I could easily do the six kilometers that I habitually use for comparable test in three seconds less than my personal record which was done on a powerful Laverda Jota, which I found to be somewhat constraining on the winding climb.

The next day I returned with the other Pantah, the 582 cc, already broken in, and I could despite a strange combination of tires just about equal the times of the previous day without the motor going past 7,000 r.p.m. and  almost always shifting at 6,500.

Later we will talk about the stable road holding, braking and rigidity, but I will say here that as a half-liter sporting bike, there is no machine more apt for serious sport riding than the Pantah.  On designing the Pantah, knowing that the Italian bikes, with their inevitable disadvantage pricewise in comparison to Japanese bikes, which are only sold when they stand out from the competition, there can be no doubt that they were thinking about roads in Bologna.

 

TIME TRIAL PERFORMANCES 

Stop watches talk and with the Pantah the watches have been very eloquent, as much in the mountains where agility, downslopes and braking performance count a lot as in the less subjective maximum speed test and the kilometer long acceleration test from full stop.

The Pantah stood out in all of them, demonstrating the most complete and efficient sports production bike tested in the long distance section.

In a hand to hand with the Yamaha RD-350 tested in the previous issue, the Ducati showed itself to have a noticeably higher top speed, although with less acceleration.  The Yamaha, with 49 hp and 50 kilos lighter, has a very short gear ratio and a six speed manual transmission, while the long fifth gear of the Pantah spoils its acceleration from rest to one kilometer.

With a round trip average of 183 km/h (113.7 mph) with two kilometers to build up speed, the Pantah proved itself to be 9 km/h (5.59 mph) faster than the Yamaha RD, and 11 km/h (6.8 mph) faster than the Benelli 654 four cylinder of the shake down test of the last issue.

The up to now fastest of the half liters on the Spanish market, the Benelli 500 was 13 km/h (8 mph) slower than the Pantah.

If I have started talking exclusively about performance and road holding, it is because with a 500 cc with short handlebars, fairing, tilt back footrests and a price of 525,000 pesetas (3,155 euros), the horse power simply has to be converted into billiant performances. If not, the Pantah would be a cosmetic café racer instead of a real Thoroughbred.

We have not been able to get close to the performance published in some of the “patriotic” magazines of Italy, but Andrés Ruiz has inspected the conduct of a Pantah of the Ducati SS series in Madrid, and his conclusion is by polishing the roughness and irregularities of the inlets and outlets you could gain a lot.  With some tuning up to improve the  engine breathing, I think that the Pantah would really be capable of reaching the mythic figure of 200km/h (174 mph), no man’s land up to now for half liter street bikes.

But a piece of advice for Pahtah owners: wait until after the 2,000 km. (1,242.7 miles) break in period is finished.  The pistons and cylinders of Gilinosil have to be broken in completely, so do the separable connecting rod bearings as well.  The London based magazine, Motor Cycle News, only got a top speed of 173 km/h (107.5) from the Pantah, writing it off as a disappointing bike and one with an idle so slow that they had to run the speed test in fourth gear.

Two months and 8,000 kilometers (4,791 miles) later, the very same bike was clocked by MIRA at an average of 184 km/ h (119 mph) with a top speed of 192 km/ h with a favorable wind.

Conclusion?  Well, the Pantah, during the break in period, is so-so and slow, especially on long runs.  The piston cylinder tolerances are very tight and just like the BMW, the Ducati Pantah runs much better after 10,000 kilometers than after 1,000.  However, once broken in, the Pantah rocks.

Despite its brilliant performance, it is not noisy or difficult or uncomfortable to handle.  The motor runs as smooth as silk, so much so that at the beginning I said to Pep Giralt that it didn’t seem to me to be very fast: I told him it wasn’t a bad boy.  And it isn’t.  The acceleration is progressive and uniform without any jerks, without any explosive jumps…just like the 900 SS, but proportionally more powerful.  I remember the first time I took a Ducati 900 SS out on the road.  I had the feeling that the motor didn’t rev up quickly enough during the first run, but because I was the first to break in it I didn’t have any complaints. 

There are bikes that seem very fast riding around on the street, generally four cylinder with a kick, but in races or in timed tests it turns out that the pick up sensation is just that, an acoustic effect.  The V-Twin Ducati, like the old Vincents, never sounded especially fast and never gave the rider a sensation of explosive power…but stop watches don’t lie.  There are showy blast offs and discrete blast offs.  The Ducati Pantah is a discrete blast off.

 

ESTHETICS

Beautiful?  Graceful?  Thoroughbred?

You have to decide before testing a bike with a simple glance, because once you have experienced what a Pantah really is…once you have shared the enjoyment of a mountain curve with one, the Pantah will seem impeccably beautiful.

The line is bold, aggressive and extremely Italian, although the seat cover is classic and modern at the same time, especially with the single seat (the cover can be taken off easily converting the bike into a two seater.)  The side pieces are aerodynamic and cover the upper part of the shocks, like in the current 500 of G.P., but the seat itself reminds us more of the Hailwood 900 SS than the Mamola RG 500.

A large part of the esthetics of the Ducati depend on whether or not you like the somewhat disproportionate fairing and the high windshield.  At first look, the fairing seems excessively big, but wind tunnel test have proven its efficiency.

The saddle is not especially low, but it is sufficiently narrow so that almost all riders can plant both their heels on the ground.

Personally I would have preferred a somewhat less bulky line and with the fairing more coupled to the bike, but with each kilometer it seemed more beautiful to me.

ENGINE AND GEARS

Ducati didn’t invent the Desmodromic valve, but they are the only ones that have made it work in road and street bikes.  Norton experimented a little with it, but when they came to testing the Desmodromic engine, the veteran single cylinder Manx was already so out of it that gaining a little more horsepower wasn’t important.

Until the arrival of the Honda G.P. with 4 valve cylinder heads, the Desmo 125 cc was starting a revolution.  In 1958, five Ducati Desmos took the five first place places ahead of the only MV that classified in the Grand Prix of Nations in Monza  (a 125 CE) beating even Count Agusta, himself.

There are a lot of advantages with the Desmodromic motor.  There is no fear of a costly collision between valves at high speed and there is no possibility of a shock between a valve and a piston if the gears lock up.  It also eliminated the power loss caused by the strong springs needed to close the large valves and high RPMs.  In addition as it can guarantee an instantaneous closing of the valves, it can also use long lasting cam shafts.  Once they asked Taglioni why he continued to be faithful to Desmodromic motor, he answered in poetic rhyme, “desmo al minimo no se sente, al massimo non mangia niente.”  That is, the idle is quiet at high speeds of rotation and doesn’t absorb power.  However, the scandal and vibration of the axle gears whose siren-like noise has always been part of the Ducati patented noise, destroyed ​​the myth of the mechanical silence of the Desmodromic motor ... until the arrival of the Pantah.

The Pantah is so discrete that while idling there is little noise and vibration that at times it seems as if the motor is turned off.   This mysterious word “Desmodromic” only means that the valves are closed directly by the cam shaft, through rockers controlled by the cam lock.

The maximum power of this motor (74 mm x 58 rm) is a respectable 52 horse power at 9,050 rpm, but when I spoke with Taglioni the last time, he told me that they had gotten up to 70 horsepower at 11,000 rpm with the motor prepared and with 40 mm carburetors.   The version originally presented in Cologne in  1978 was that one with 70 horsepower at 11,000 rpm, and Taglioni still wanted to market this brand new version… that was capable of reaching a speed fast enough to have made Rollie Free change his Vincent 1,000 for a Ducati.

There is no better guarantee of force than a bike designed for roads.  The 52 horsepower version must be quite far below the limits of force, although you shouldn’t talk about this until they have done very long tests.

You never know if a factory model that seems outstanding will be the similar to the bike that is finally sold.  The Pantah of Luis Miguel Reyes and Alfoso Durán of the National Endurance Test, however, seemed exactly the same as the street Pantah, with the exception of the increase in engine capacity.  Plus this bike was able to give the Yamaha OW-31 of Grau and Alguersuari in Calafat a run for the money and was only surpassed by the 900 SS of Mallol and Tejedo in Jarama.  And we have yet to see any crank pop out to catch the sun.

 

The Neoprene belt drives have come through very hard and long tests without breaking including even some 120 hour tests with the throttle wide open (not on the same bikes for 120 hours, however) with flying colors.  

The possibility of one breaking haunted Taglioni so much that he dedicated his professional life to perfecting a distribution system that eliminated these ugly disasters that destroy four-stroke sport bikes.

Taglioni is a very conservative man, so much so that the ignition systems of the racing Ducatis always had breakers after a couple of failures with the Ducati Electronic ignitions.  I think it is Taglioni’s conservative nature is the reason why you can go 20,000 km. without changing the toothed belts and also why the price of the belts is so low and why they are so easy and quick to change.  Normally, at 20,000 km. the owner of a Pantah is going to want to adjust the valves (which is neither easy nor quick) and the belts can be changed at the same time.

Moto Morini has for many years used a toothed belt to drive it camshaft, and the smaller of the two factories in Bolonga also specifies an period of 20,000 km.  Toothed belts tend to last twice as long in cars, but it is better to be safe than sorry…and I can’t imagine anything sadder, mechanically speaking, than to have a belt brake on a Pantah at 9,000 r.p.m.  Changing the belts at 20,000 km. is a good guarantee of a long mechanical lifespan for the bike.

The five-speed gear box has a gap between the fourth and drive that adds up to a loss of 1,500 turns. This is the most critical thing about the Pantah, and it forces you to drop down a gear to get up a small hill or to pass a car when you going at high speed on the highway.

With the 582 cc increased version, this is less bothersome, but it is a pity that the Pantah doesn’t have a six-speed gearbox. If it were possible to join the fourth and the fifth somewhat more, you could take advantage of the power of the motor much better.

The change, by itself, is a minor touch, a hair quicker and more precise than the gears on the Laverda, for example, but much better that those of the Benelli and the Morini 500 in regards to the quietness and speed of selection.  One of the three bikes test had a tendency to make noise when shifting between second and first, but it seemed to be a problem with the gearbox, because with the other two bikes there was no noise or slowness.  The clutch has a normal feel without being too stiff or difficult and during repeated one kilometer acceleration tests from dead stop it stood up without any sign of problems.  Normally test bikes get a real beating on acceleration test, but this time, with bikes that were not “official” I went a lot easier on the clutch, and this is why I cannot personally vouch for its strength in the face of rougher use, but up to now I haven’t read or heard anything worrying about the Pantah clutch.

SUSPENSION AND CHASSIS

Of the three Pantahs that I tried out, the one of Fargas had the most correct suspension, which is not surprising because this bike has been used by some of the most demanding Spanish Ducati fans.  The other two were a bit soft in the front fork and dipped annoyingly during hard braking.  It was a question of changing the oil for one that was denser and experimenting until you find the combination of quantity and stickiness that you like best.

The gas filled Marzocchis with five suspension spring settings are stiff even in the soft position.

I like a stiff suspension in front and in back, like the Fargas 582, but in the other Pantahs, the combination of stiff suspension and soft fork ruined a little the feeling of the bike.

When you go really fast on the Pantah, the Marzoccis work fantastically.  They are designed for hard riding even though the Pantah is a purebred super sport bike.   However, these stiff shock absorbers and the hard saddle make the Pantah an uncomfortable bike for riders who are used to Japanese bikes.

Although the Pantah is not an ideal bike for carrying passengers, the Marzocchis didn’t bottom out even on bad roads when I rode two on the bike.

I have tried the Pantah with three distinct sets of tires, Dunlop, Michelin and some racing tires (logically on the Fargas bike)  Although it seem ironic, I must say that I haven’t the bike with the Phantom the tires that are on almost all the bikes exported to Europe.  However, the bike performed excellently with both the Dunlop and the Michelin.

Despite that, in the final analysis the best tires in the world and the perfect suspension do not guarantee the rigidity and without rigidity there is a bouncing that spoils a lot of machines with pretensions to be sports bikes.

The torsion points are usually the steering tube, the rocker shaft and the swingarm itself.

At Ducati they haven’t allowed the Pahtah to disappoint in such an important detail.  As with the Velocette Nevom of the 60s, the frame is virtually without curves.  Like the Norton John Player of the Formula 750, it has a trellis or multitubular chassis, and like the racing Norton itself, it has a swingarm integrated into the gearbox.  This reduces the weight and complexity.    By placing the swingarm pivot so close to the output pinion, you reduce significantly the imbalance which cuts down on the variations in the chain tension.

In a time when racing bikes tend to be focused on a rectangular swingarm, Ducati remains faithful to the tubular swingarm, but with a diameter that is constant to the end, and without ending in a flat and flexible section like the Japanese bikes do.  The swingarm of the Pantah is a strong as that of the 900 SS, which stands up to at least 90 horsepower without problems.

The Ducati Pantah is so superior that you can only get close to its limits of rigidity on the circuit…and from what we saw in the Spanish Endurance Championship, Durán y Reyes didn’t seem to have any problems of this type.

The difference in stability between the Pantah and the Ducati Desmo 500 of the two cylinder transversal bikes is like day and night.  While all of the Twin and Desmo 500s had a tendency to be unstable on fast curves, the Pantah took them like a train on tracks.

Getting off the Pantah to ride the Yamaha RD-350 (I tried both of them on the same day) was an pleasant experience but difficult to analyze.  The Yamaha with cantilever suspension bounced less over continuous bumps (Montseny) but without any quick curves there was no way of seeing which bike was more stable in the back.  The Ducati did win as a whole due to the lightness in the back of the Yamaha.

It’s very difficult to compare the Pantah with other bikes of its cylinder capacity because the Pantah reaches speeds that they others can’t and even when it does it continues to be stable and sweet to handle. 

 

BRAKING

The Pantah loaned to our colleague, Andrés Ruiz, by the Madrid dealers, Ferrero/Carrero, seemed to suffer from a tendency to raise up in the back when braking.

Can it have been a consequence of not having broken in the rear disc? Or maybe a defect in the disc?

I don’t know, but the three Pantahs that I’ve tried have braked like GP bikes.  Even with quick stops and after shifting down to first gear, I could use the back brake sparingly without having rebound problems.

In addition in front the only factor that limited the efficiency of the brakes was the front end dive on the test bike.

The braking system is from Brembo, and Brembo is a synonym of perfection.

 

FINISHING TOUCHES AND PRACTICAL CONSIDERATIONS 

The instrument panel is tasteful and the gauges are easy to read, although both of them exaggerate.  In order not to ruin the aesthetics  and the aerodynamics of the Pantah, there is a folding handle to put the bike on the stand for subtle originality.

The Nippon-Denso switches team included the bike stand and put the controls not at odds as usually happened with certain Italian brands like Morini that remained faithful to the more difficult to use Italian accessories.

Evidently Ducati had thought about putting a side stand on because there is a warning light that says Stand, but unfortunately there isn’t one, which would have limited the tilt angle permissible.

The bike is very easy to mount on the stand, but due to its reduced turning ratio, stationary maneuvers are not as easy.

I didn’t find any ugly details, no Italian junk hidden under the gas tank or the saddle to make me say as I have so many with non-Japanese bikes (excepting BMW, of course) “What a pity they didn’t think of that.”  Even the light is a super powerful 55/60 W with a well defined beam. They have thought of everything!

The air control knob is located in the windshield in a difficult position, this is true, and the front mud guard is badly fitted to the bike.  It’s too high and separated from the tire…but if we have to look for defects in such petty details, it means that there aren’t any important ones.

Ossa, Kawasaki and Yamaha have made two-stroke engines with brilliant acceleration, but of these three brands, only Yamaha still has a two-stroke medium displacement model capable of running with the Pantah in production.   Hon­da and  Kawasaki have four-stroke bikes that get close to the performance levels of the Pantah, but without having the agility and rigidity for sport driving, and Laverda, with its roaring and antisocial Montjuic with open megaphones and unfiltered carburetors, has the same power (52 a 9.000 r.p.m.) and is 20 kg (44 pounds) lighter... but the Montjuic can’t go down the street with its scandalous megaphones.

So we arrive at the conclusion that the Ducati Pantah is the new queen of the 500 sport bikes of the world market and as an inevitable consequence, one of the most expensive as well.

Those who buy their bikes by the kilo, by cubic capacity, or by the number of cylinders will find more attractive alternatives, but inside of the classic capacity of 500 cc, I can’t think of any bike more sportive and at the same time more civilized, or in other words, more complete… than the Ducati Pantah!