Cycle News - Archive Issues - 1980's

(Continued from pa!5.e 56) the side spars. The steering head is made from sheet aluminium welded into a Refly box section. The rear suspension Gallina says "Is more like a Kawasaki or Honda design than Suzuki's 'Full Floater,' but it is being remodeled for '85 a Gallina is convinced that the Suzuki system is the best. The way that the bridge section that holds the rocker arm is boiled on is an advantage. The rear section Of the machine has already been changed once after initial tests at Misano and during practice for the French Grand Prix at Paul Ricard. There it was found that the relative position of the swinging arm pivot and the gearbox sprocket was wrong. Ex-Grand Prix racer Gallina himself tried the bike at Misano. "It was certainly good, but much faster than I am now," said the team manager. "I used to be quite good on a 750 Yamaha but these 'machines are so much better and you have to lean them past 50° to test them and I'm not up to that." The special nature of the TGA-I is not confined to the frame as the tankseat unit and the fairing are unlike any other Grand Prix machine. Made in carbon fiber, these components are sleek and functional. The fairing has gearing is accomplished by using a toothed belt and having the handlebar column offset to the rear of the steering column. A larger pulley wheel is filled to the steering column than to the handlebar column. Although the TGA-I .wa never raced through the sea on it was tested at most circuits, acruing valuable information for '85. Franco Uncini's crash at Paul Ricard on the conventional machine put him out for. four Grands Prix and this upset the program somewhat, buta winter's testing should put the bike on the grid. Gallina sees the TGA-I as a step forward for several reasons. As a practical engineer who knows what it takes to win races, he appreciates the flexibility that the construction system gives him. It is not a complex design by anY means and well within the technical ability of the team. The fact that it can be altered to accept other engines is important as Gallina is a realist and knows that he may be using a different make of engine next year as his team is now based more around sponsorship than factory backing. He would like. to stick with Suzuki though and at the German Cologne Show in Septem ber received assurances from Suzuki thata brand-n.ew Grand Prix engine was on its way. The Gallina Suzuki designed by Roberto Gallina has main frame spars made of machined-out aluminum struts filled with aluminum honeycomb and topped with sheet aluminum. hugeair escape passages for the radiator. The radiator. itself is built in a V and takes air in from behind the front wheel in the normal fashion~ It exits through each side of the fairing long before it gets the chance to he'!t the engine cases or get sucked into the engine. To create the superb fiber work a positive replica was first made in aluminium and plaster. From that a half model was made in wood and doubled on a copying machine, to ensure a perfectly-symmetrical arti- . cleo That was used to make a negative mold out of fiberglass and hence the first fiberglass fairing was produced to prove the ,mold befoTe repeating the process in more-expensive carbon fiber. Underneath the forward end of the tank and seat unit lies the other, uni. que feature of the machine, tlJe geared steering system. It is one of Gallina's babies that he likes to play down and almost dismiss: "It is not necessary to the rest of the machine and I don't think that the riders like it. Franco tried it but found it difEicult to get used to. " The geared steering Gallina tried before, when 16-inci} wheels were .~ first used. The idea is that by givirig the handlebars a greater mechanical advantage over the front wheel, a wider front tire can be used without the steering feelin~ too heavy. The 58 The continued development of Suzuki racing engines is even more important to the British Suzuki importers Heron who are mounting a full-scale Grand Prix effort next year with TT winner Rob McElnea as their number one rider. They contested several GPs through '84 and on several occasions used their latest· creation, a plate-framed machine using an aluminium composite material. . . The aluminium composite is made up of two sheets sandwiching an a'luminium honeycomb, all three bonded together. The frame construction features two boards, one on either side of the engine with segments cut out on a band saw to give room for the carburetors. The boards are cut and re-glued where they have to bend, as they turn in towards the steering head, for example. The material cost of the bare frame is only about SIOO and construction requires no high-tech knowledge. Cutting can be done on a band saw and the open edges are finished with the application of a filler which performs like car body putty and adds to the structual strength. In bending, the skin that wi II be on the inside has a strip cut out and the honeycomb collapses slightly as the bend is made. The inner skin is rejoined by an overlaying strip of aluminum glued to the skin. Gluing does not reql,lire a The Heron Suzuki machine's frame is built of aluminum composite made of aluminum honeycomb sandwiched between sheet aluminum bonded together with trick glue. Rob McElnea did the test riding. special environment and cold curing is quite possible, allowing paddock repairs if necessary. The Heron project has proceeded along very logical lines, attacking one unknown at a time. The composite frame was a direct replacement for the tubular aluminium predecessor and was tested back-to-back with a conventional bike. Other advances tried on the Heron project incl ude a peripheral disc'on the front. The disc is bolted to the wheel rim and this improves the ratio between disc and wheel and removes the necessity for a disc carrier. The next logical step is a much-lighter front wheel with no requirement for the spokes to be capable of transmitting torque from center to rim. The weight of the disc has already been greatly reduced by using carbon fiber and Lockeed has been producing all the discs and special calipers, working hand-in-hand with Heron. Carbon fiber front discs were also used through '84 by the Chevallier team and Didier de Radiques reported first-class performance. The single front discs were conventionally mounted, and to get the maximum performance two calipers were mounted on the one fork leg. The forward caliper is a specially-adapted four-pistOn Brembo and the rear a similar twin-piston unit. The adaptation performed by Chevallier involves adding finning to the calipers to help cooling because carbon discs operate at much-higher-than-normal temperatures. To call these fiber discs is something of a misnomer as the manufacturers prefer carbon-carbon, being purely compacted carbon strands with no resin. The flow of heat through the discs tend to be along the length of the carbon strands and hence the hottest part of the disc is the perifery. Replacing two iron discs with a single carbon unit cuts the weight by 75% and as this is unsprung weight the advantages are doubled, making thejobof the suspension much easier. Carbon discs are still in the development stage and De Radigues had to -retire from the Swedish Grand Prix'. with his 10mm-thick disc worn to a 2mm wafer. Anderstorp is particularly hard on brakes and after suffering wear during practice a new disc was used for the race. U nfortunately only one of a slightly-different quality was available and it did not stand up to the hammering. Disc overheating can be seen even if wear rate is not obvious, Discs that are going to fail start to look like puff pastry at their edges as the layers of carbon filaments become detached from each other. The Chevallier team have done a - great deal more than just add carbon discs to the front of their three-cylinder Hondas. French constructor Alain Chevallier has only used the Honda engine and the rest of the machine is built by him and his team. Chevallier has built 250cc and 350cc frames for several years, firstly for his brother Olivier - who was tragically killed at Paul Ricard - and since then the team has included Grand Prix winners Didier de Radigues, who finished second in the 1982 350cc World Championship on the Yamahaengined Chevallier, and Jean Francois Balde. His frames have always been ma.de from chrome-moly steel tubing with a high content of titanium parts, including.exhaust pipes. In swapping to the 500cc class Chevallier has retained the frame concept, incl udinR the rocker arm rear suspensIOn whlch features adj ustable geometry thanks to an eccentric rocker arm pivot point. The bikes worked well from the start and de Radigues finished fourth in the pouring rain at the first Grand Prix in South Africa. In the dry though there were rear-wheel traction problems that were only cured by moving the swinging arm pivot forward and lengthening the arm. So impressed were Honda with the Chevallier team's efforts that they provided the team with a works engine for the second half of the season. ChevaIIier hopes for continued works support from Honda in '85, but it is quite possible that his very-talented Belgian rider may be bought by a wealthier team. Chevallier admitted that it cost him 2,000,000 French Francs ($220,000) to run his team for the year and that did not include paying the riders. The special machines from Chevallier, Gall'ina and Heron have still to win a Grand Prix and the trophies stay in the hands of the works team, but even they have their technical problems and one of the features of this year's 500cc World Championship struggle had been the weekly . indecision in the Honda camp as to whether Freddie Spencer should ride the old three-cylinder NS500 machine on which he won the '83 World Championship or the new V -four. Spencer won the Italian, French, and Yugoslav Grands Prix on the four but reverted to the three to win the German and Belgian rounds. This decision was not taken lightly as there was a great deal of reluctance from the factory to let Spencer use the three as doing so meant a great loss of face for the company. There have been several problems with the four, splitting into two main groups; the engine trouble that (Continued to page 60)

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