Friday, March 2, 2012

Ducati 750GT-Mechanical Art

The round case bevel engine is the loveliest piece of mechanical art ever put in a motorcycle frame. It looks like a slice of a 30's aviation radial! It had Contis which sounded like armageddon. The most wonderful sounding motorcycle I've ever heard.

The super torquey engine pulled beautifully and made it a joy to ride. In its day, this was the hottest motorcycle money could buy. After riding a 1967 Triumph Bonneville for years, it was an absolute revelation. It is on a whole other level in terms of handling stability and performance. The frame is the most solid of its era. It does feel very long and high, and with shockingly little steering lock, it's a real handful at low speeds. Until you get used to it, you are always whacking the steering to the lock and then having to stick out your leg to keep from falling over.
On the open road it's just a joy. It feels soooo stable on very high speed corners. Trying this on a contemporary Japanese bike would be absolutely terrifying. It really outclasses anything from the 70's, except maybe a Guzzi V7 sport or LeMans, but the Ducati engine is in a class by itself.

Road Test Cycle Magazine 1973

If you are at all a dreamer, as I am, you will have begun to detect references of the Ducati 750 to ideal bikes: exotica, classics and the like. One such reference might be to some legendary handler of yesteryear. Classics are classics for reasons. The '37 Velocettes are more desirable than others of their day. Velocette won more races than its competition, and due to ability in handling, power and reliable, quality workmanship, it was in the forefront of its day. Likewise, every year has its own classic models, the result of careful race bred R&D. The ideal bike that I mention is nothing more than the new bikes that are not classics yet, because we have no view-scope of time experiences to examine them with. The attributes of such a beast are describable, however, subtle as they may be, and certain present day motorcycles are rumored to fit the parameters. Nortons, BMW's, Moto Guzzi Sports, MV 750's to name a few. And the Ducati 750.

The bike we tested came from Ashford Engineering in Westchester, and was kindly lent for riding and photography by Ed Young of DEVOn, Pa.

The Ducati 750 bike looks like nothing else, not even Harley 750 racers, to which it is closest in concept. There is too much air above the crankcase and behind the front forks to look like the compact Harley. The "V" angle is greater also, being 90° and also tipped forward for cooling reasons. Yet there are similarities. Both bikes are hardly wider than a single, both are chain driven, both are light. And the Ducati feels the way I expect a Harley racer to; that was the best surprise of all.
The airy front end and the alloy forks make the front of the bike appear very light. Maybe the chopper folks will keep their hands off. The rear of the bike is visually understated, as on almost all bikes. It has its worthy aspects also. Upswept pipes suit contemporary styling, but they suit purpose first, for this is a bike you would drag straight piped with. The Borrani rims and Marzocchi shocks do nice things for wheel chatter. Probably the most unique aspect of the rear of the bike is the swing arm adjustment. It is an infernal unit that allows easy movement of the rear wheel and also easy alignment of the wheels. The swingarm rests near the ideal horizontal, as close as possible considering that two riders could double the weight on the springs. Likewise, the crankshaft is apparently on the line between the axles, as closely as that can be measured. These are two of the more important design factors for handling. Welds appear to be almost contoured, though they are not, of course . Beautiful craftmanship has gone into the frame. The glass and paint are an entirely different matter though. The glass is pinholed. The color is dull, the decals are cracked. Likewise, the seat material is apparently cheap. Yet the seat and tank are comfortable.

The design is good but the materials are inferior, at least in looks., The bike is, of course, 2000 miles old, and that means weather. Still, the finish is poor. The polished side covers seemed a bit blatant also. The dashboard was heavy handed. Padded plastic luxury belongs on some other bike. I much prefer headlight nacelle mount or individual mount instruments with the idiot lights in the speedo. The bike is so straightforward aside from this that I was really struck by it. Maybe it just reminds me of Detroit iron. The only iron on the Ducati is in the cast iron cylinder liners.
The engine is of alloy and some of the castings are neat, such as cam-cover name-plates and the finning that is different on each cylinder to help proper cooling. The engine seems uncluttered, to me, the way a BMW engine does; though not easily seen in pictures, the casing really encloses the works and makes the engine into a unit that is clean and bright and oil free, even though vertically split. There is room to see around and behind things also, and to get your fingers in for cleaning and working.
The result of all this examining of detail is that you begin to realize the materials and design are chosen for the kind of job they do. The next step is to view the entire package.

First impression is that the bike is big, gangling, but that there is not much to it. Indeed, the forward cylinder makes the wheelbase long. And with the vertical one the bike is tall, tall enough to slip the air cleaner in under the gas tank and not have it noticeable. There does not appear to be much in behind the side covers besides the rear carburetor. The long wheelbase smooths the ride, for sure, but does not slow the handling down much compared to the competition.

The bike is certainly a pure design. The powerplant concept was, I would guess, the origin for the entire project. The crankshaft position, the inclination of the engine, the swing arm angle, and the steering head position and angle are not all that variable for designing optimum handling. And nowadays optinum handling is not that much of a mystery, especially for a firm such as Ducati. In addition, swingarm length, shock absorber angle and suspension travel further dictate the arrangement of this bike. In designing the frame itself, Ducati did, however, fly in the face of accepted practice, for open-cradle frames in which the engine cases complete the loop are considered susceptible to flex. Ducati has succeeded by providing three backbone tubes spanned and joined by two cross tubes. The steeringhead and swingarm do not move relative to each other. And the proof is that not only is the 750 the best handler I have ever been on, but the factory racer, which has a very similar design, is a winner by virtue of its handling as well as by its powerplant, which just is not any 150 horse, fire breathing, ten cylinder, two-stroke. It is supposed to be one of the best handlers on the circuits today.
The suspension is also unique to this bike, being designed especially for it. Marzocchi created forks and shocks to Ducati's design. Lockheed created a disc b rake to Ducati's design and Marzocchi's fork. Even two-up the feel is light. At a stop the bike is easy to manage, even with 175 pounds on back. There is no pitching or yawing or wallowing in corners. The feel is uncannily accurate, in fact. Reading the speedo is far more scary than riding. The brakes are good; the engine power curve is absolutely delightful. It is wide and torquey like a Norton, only more so. The brakes, as I said before, are a Lockheed unit. The disc is cast iron. It rusts, but works better than stainless. They were designed for the bike and provision is made for adding one on the right leg as well as the left. My only gripe is actually with all disc brake units. The owner is using a very low rise Z bar, not as a custom touch, but because even with BMW touring bars he could not fit the disc brake hydraulic reservoir in beside the padded dash. This has been a problem on several bikes I have encountered. Maybe the hydraulic system should be cable operated and located farther down under the head light. Reliability certainly would not be a problem. This approach to riding appears to be catching on in the U.S. and maybe someone will manufacture a decent conversion. With racers, of course, this is not a problem as clip-ons clear the instrument and there is no headlight nacelle.
So far I have talked mostly about the machine as any educated viewer might see it, and as he might guess about it having read all the other reports. The general impression being that the finish and decoration has been sacrificed to the workings of the machine.
Sitting on the bike I was surprised at the comfort. The seat was very nice with its pocket. The pegs were optimum: I could stand on them without pulling or pushing on the bars. The Z bars were even good: narrow, but high enough to save your back driving around town. The clutch felt heavier than Japanese ones, but very smooth. The throttle was not heavy and was very smooth.

The electric switches, on the other hand, are evidently terrible. I can't say for sure. I never used the dimmer, and the turn signal switch had disintegrated and been replaced with a rather serviceable home made unit before I ever saw the bike.
The choke may well be unnecessary just as with Norton, since the carb is the same on both bikes—Amal 930 concentrics. That is an unnecessary clutter just as the brake resivoir, but on the whole things are relatively simple—especially if you are used to Japanese or Lucas units.
When the bike comes off the stand one thing is obvious. This is the most solid feel ever. No rattles, no shakes. The bike is very tight and light to wheel around. Both fuel taps have reserve, so open both. They cross feed. Tickle the carbs till they weep. Turn on the key and just crack the throttle. You can even kick the bike over with your hand and it will start first try!
Fired up, the engine noise is quite low, except the valves needed adjusting. The exhaust was surprisisngly loud, but very pleasant. Pull in the clutch and think it into gear. Honestly, if the transmission was made of glass I don't think it would break 'from shifting. Between the incredible transmission and the super smooth clutch, your passenger may never notice your shifting. There is lots of torque anywhere on the power band and there is no noticeable power surge, just lots of good, lean pull.
This is no streetlight dragster, but it will cruise happily at higher speeds than most of them; even big ones. This is one reason I think the bike would be a great tour bike. The 30 m.p.g. fuel consumption seems a bit low, but I'm sure that could be improved upon. The 4.5 gallon tank gives you a 175 mile range. On most bikes that is where you need to stretch your legs anyway.
That may be true, but it won't be due to the vibration. Even looking for it, I could not detect anything more than a hint that the engine was ever running by feel.
Indian made a 90 ° V shaft drive bike for the Army in 1941. They claimed the 90° V was the smoothest way to go. Moto Guzzi is the only one now doing it, as far as I know. They claim the same thing. Theoretically, the 90° V should be the smoothest arrangement. But Ducati is the one that proved it to me. When you hit the throttle since the crank is not in line with the bike it doesn't roll as the other two do, and the engine revs a lot freer and faster than the other two do. And with the chain drive on the Ducati, shifting is an absolute dream; no clunk, no nothing except confident, effortless shifting, and, in my experience, the smoothest ride of any bike except a four-cylinder.
What's left to elevate this bike into the range of exotica? Certainly not the price. $2089 is less than a Norton and about the same as a BMW 600/5. Mv's, Guzzi Sports and Mammath's are hundreds and even thousands of dollars more.
What makes this bike a classic is its purposefulness and the degree of success toward achieving its purpose. Handling must be the most inclusive single word to describe a motorcycle. Speed, power, ride, and cornering ability are all part of handling, that this bike has in Spades. But the aim of the designer was a bit more than that. He tried to apply all his experience to comfort, ease of operation, and a high degree of quality as well as to basic handling. Everything about the machine is of excellent quality.
In this respect he has come a long way toward my dream bike. The fact that it is a joy to drive can only bring it closer. Even with its glaring faults, and to me they are glaring, someday I might very well own a Ducati 750.

Source Cycle Magazine 1973

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