For three bikes which have concluded the Paris Dakar were taken, as a starting point, the engines of the XT 600 1989 and the TT frame 600. Interventions on the engine were not radicals. No additional cilindrrata, but only a particular tuning.
The decision not to proceed with the preventive replacement halfway through the race the engine (that would have implied automatic disqualification from the category silhouettes) obliged to maintain normal stresses and sizing. A slight crimping of pipes, an oil cooler (the Yamaha 750 Mono five valves), the kit camshaft BYRD to process the TT 600, intake filter box redone to accommodate the paper element of Renault 12(the only one to be in every corner of Africa) and an accurate fuel tuning, are the few interventions carried out on the engine. The exhaust system was built from scratch on the BYRD, competition exhaust system with a megaphone and end friction Cone, It's sheet 0,8 mm thick. The collectors into the cylinder were kept in two pieces (one for valve) It was connected to a silencer for European transfers.
The ignition was the original of the former as well as the cylinder piston valves and cylinder head; the latter equal in engine engine XT 1989. The choice of layered cylinder rather than with TT galanico 600 was made to enjoy greater reliability towards the inevitable intrusion of sand. The Carters were sandblasted and painted external transparent but only for aesthetic reasons. Carburation was then retouched with a decent minimum and maximum jets enrichment.
The original Crown was replaced with a steel combined with an RK chain Chiaravalli self-lubricating o-rings, leaving only the original pinion. Also noteworthy is a reinforcement for post transmission control, with a lock washer against the bumps and scratches. The lubrication of the engine and gearbox was reliability at a good grade as the Shell Helix.
During the race the maintenance of each bike to required three candles, four oil filters and three complete sets of chain sprocket Crown, countless air filters and gasoline and a complete carburetor for motorcycle by Marcaccini (paid well 4000 FR. the Yamaha Sonauto).
One mounted he inexplicably began to crank the engine regularly nor thorough cleaning has managed to bring it back in starting conditions.
Also this important component has been completely redone, depriving him of any links superfluous and doubling it in full. Then: two coils and two units.
Headlights, two halogen lamps of the Fiat Ritmo were included in a fairing bracket that provides a separate regulation for the inclination of the beam, so you always get an adequate lighting in long discussions of the suspension. Sealed battery adopted, He provided the energy to pump gasoline from a Yamaha Tenere 600: universally recognized as the most reliable by the people motociclistista of Dakar. For navigation were mounted electrically operated Road Book of MD, the original wave trip master XT 600 R and a compass Aeronautics .
The base and the Yamaha TT 600 the front was obviously reinforced with welded handkerchiefs in the Steering area, but also to increase you search 1 liter engine oil capacity that circulates inside the tubes. The bow steering profit was diminished with the usual placchetina by welded tube, measured the outer corners has a width of 50 mm instead of the normal 20 mm. This is to prevent, in case of a fall, the fork tank backgrounds. The back instead was redesigned is built completely.
Swingarm attacks. However, more work was required by the design and construction of the swingarm. Longer and well 150 mm compared to the original, It was built in Carpental, the outdoor unit is 80 × 35 mm.
The attack to the chassis is done through two plates billet and combined with two arms for welding. As you can judge from the photos the swingarm denotes a truly fine finish. It should be remembered that all the workings of chassis that have been carried out with the help of specially constructed masks. Jack stands, particularly important, lateral type and placed on both sides of the bike. If lowered simultaneously, the rear wheel stays off the ground, allowing for easy replacement in the same. On the left keeps the original crutch enriched with a wide base of nylon to prevent better the Foundation on sand. On the other side we find the type container gantry mounted by the official Yamaha. In fact was created on the basis of some photographs.
The ward is served by a traditional Kayaba fork suspension, official backgrounds with 43 mm and from Mont Ohlins devoid of external hydraulic adjustment in compression, with leverage of progression of TT 600
The beautiful fork is fully invoked by full regarding pictures and pumping elements and is equipped with quick release wheel (Although, its usefulness now that the mousse have taken over over traditional). Within the pumping elements is mounted a cavitation system for hydraulic oil. Longer final calibration tests instead mono shock, which has been called a few days before departure for Paris. The Reed inside works set in specific Ohilins oil and in tune with a spring from 9,5 kg (slightly more closed to the weight). The internal pressure is 15 atmospheres and we must specify that during the race he never made it necessary to replace the damper unit in any of the three motorcycle,
Billet fork plates that if working 2 Avional blocks 24, unchanged steering geometry, but increased the height of the same: 38 mm for the upper and 40 mm for the lower wheels were assembled in the workshop of Wild Team with hubs and spokes from officer, and normal production circles Takasago. For the latter, however, it had to buy non-perforated for RADIUS, that was done after the specific drilling required from the hub, designed for rings DID.
And caps wheels and swingarm Marcaccini's Malik went to the specialist Poggipolini, that takes them in steel, While the nuts and bolts, we tried to keep the original, judged excellent. The brakes were supplied by BYRD and stand before a nice cast iron Brembo disk from 300 mm floating flange mount widely breached and made of light alloy. Later comes to help to curb the over 160 kg dry weight of this special steel disk 230 mm coupled even it has a two-piston Nissin.
The handlebars are the original controls of the XT with electric ones modified functions. Only the handlebars, one Zachariah sets our have chosen for its exceptional strength, It is mounted with a particular bridge, always fold connecting the two fixture brackets to the top plate. Thanks to this particular Marcaccini in 1988 could conclude 1000 km of a leg broken in half despite the upper triple clamp, with only the aid of a nylon strap provided by Clay regazzoni.
Finally we left those who are perhaps the most important pieces to have functional and at the same time a motorcycle ride: receptacles for the location of 60 l of fuel which you must carry during the African Marathon. Build tanks for an enduro is not an impossible task, but do it for the Dakar, and then in the most robust possible is another deal.
We wouldn't want to expire in rumors from shopkeepers, but the same official complained the last Gilera blazoned Paris Dakar, leaks from the tanks that the poor mechanics have had to repair often. All superstructures for their special are their most successful details. Made of folded aluminium sheet, shaped and welded as few but plumber can do. Please note that the bike protagonist of the service, though restored is still the bike that led Mabuya from Paris to Dakar. Coming to the point we find the two front tanks, for a total capacity about 45 Lt. easily removable with a link to communicating vessels for an immediate reading, while driving, gasoline still available.
The draught of the precious liquid takes place thanks to the electric pump already mentioned, assisted by a trigger hand pump type rubber speedboat. Under the seat, covered in faux suede, for better grip on the backside, There are others 15 Lt. of fuel. The rear locks the rear cradle and comes with two handles very useful in cover-ups.
Within these enclosures was introduced a special foam to avoid violent rinses, otherwise dangerous in driving, and especially when cornering. The water tank is placed under the engine (required for regulation) with its 6 Lt. about capacity, l’alloggiamento della batteria e un ripostiglio capiente per eventuali ricambi e attrezzi. Con la piastra inferiore, quest’ultimo funge anche da scudo di protezione per il basamento del motore.
Infine il cupolino e i parafanghi sono stati realizzati su disegno del Wild Team anche se chiaramente ispirati a quelli delle Yamaha ufficiali. Nella loro progettazione si è curata soprattutto la riparabilità in caso di incidente. E dobbiamo riconoscere, dopo aver visto Marcaccini all’opera, che tutte le sovrastrutture si smontano in pochissimi minuti. Un ottimo lavoro dunque, soprattutto in considerazione del pregevole risultato globale che non ha mancato di stupire vari esponenti della stampa straniera e mi stessi avversari.
Ed: tutte le 3 Yamaha del Wild Team raggiunsero il traguardo di Dakar, Montebelli 17°, Aluigi 28° e Marcaccini 30°.