Английская Википедия:Ducati 450 R/T
Шаблон:Short description Шаблон:Use dmy dates Шаблон:Use British English Шаблон:Infobox motorcycle The Ducati 450 R/T (road/trail) is a Шаблон:Convert single cylinder bevel drive desmodromic SOHC motorcycle produced by the Italian manufacturer Ducati from 1971 to 1974. Initially produced at the request of the American importers Berliner Motor CorporationШаблон:Sfn as a motocross / enduro motorcycle offered exclusively to the American market, and only a few hundred machines were made of this type.Шаблон:Sfn It is the only off-road racing motorcycle to use desmodromic valves.Шаблон:Sfn An optional street equipment kit was available.Шаблон:Sfn From 1972 it was produced for the European Market as a street legal on/off road machine,Шаблон:Sfn which was sometimes known as the 450 T/S.Шаблон:Sfn
Total production was around 460 machines.Шаблон:Sfn
History
American desert racers Doug Douglas and Jim McClurg had won the inaugural Baja 500 on a modified 350 Ducati desmo in 1969.Шаблон:Sfn This prompted US importer to request a 450 off-Road racer to compete with the successful BSA B44 Victor.Шаблон:Sfn Ducati employed 1966 Italian scrambles champion Walter Reggioli to develop the new bike.Шаблон:Sfn
The tank, mudguards and side panels were made of bright yellow fibreglass. Even with rubber-mounting, engine vibration and frame-flex caused the components to crack.Шаблон:Sfn
A street equipment kit was available which consisted of front and rear lights, wiring and handlebar switches. With the kit fitted the bike was not street-legal as it had no brake light, horn or silencer.Шаблон:Sfn
The engine was set too far back for the short wheelbase making the machine difficult to turn.Шаблон:Sfn With under-damped suspension and a dry weight of nearly Шаблон:Convert,Шаблон:Sfn American riders preferred the new lightweight two strokes and the bike was only imported for a year.Шаблон:Sfn
At the 1971 ISDT held on the Isle of Man, the Italian team used R/Ts, including three fitted with demo 350 cc engines.Шаблон:Sfn These machines had a modified steering head angle, high level twin silencers and a centre stand to ease changing wheels when punctured.Шаблон:Sfn
In 1972 the bike was offered with full street equipment. This included lights, horn, instruments, alternator, coil ignition and an ignition switch mounted in the headlight shell. A low level exhaust and Silentum silencer, as used on the Mark 3, was fitted. In 1974 electronic ignition were fitted.Шаблон:Sfn
Technical details
Engine and transmission
The single cylinder bevel drive OHC engine was of vertically spilt unit constructionШаблон:Sfn and had an alloy head and alloy barrels with austenitic liners.Шаблон:Sfn Ball bearings were used in the main bearings and roller bearings for the big end.Шаблон:Sfn The head used desmodromic valves. (A system where the valves are positively closed by extra lobes on the cam and levers rather than by a more conventional springs).Шаблон:Sfn Bore and stroke were Шаблон:Convert giving a displacement of Шаблон:Convert. Compression ratio was 9.3:1. and the claimed power output was Шаблон:Convert @ 6,500 rpm.Шаблон:Sfn A decompressor was fitted to aid starting and also as a method of stopping the engine as no ignition switch was fitted.Шаблон:SfnШаблон:Sfn
Fuel was delivered by a 29 mm Dell'Orto UHB carburettor.Шаблон:Sfn Wet sump lubrication was used.Шаблон:Sfn Ignition was initially by flywheel magneto. This was changed to a battery and coil in 1972 and electronic ignition was fitted in 1974.Шаблон:Sfn
The primary drive was by helical gears to a multi-plate wet clutchШаблон:Sfn to a 5 speed gearbox.Шаблон:Sfn Chain drive took power to the rear wheel.Шаблон:Sfn
Cycle parts
The 450 R/T used a newly designed single downtube frame that shared several features with the 750 GT.Шаблон:Sfn Front suspension was by Шаблон:Convert diameterШаблон:Sfn telescopic forks made by Marzocchi. Based on a design by Ceriani, they offered Шаблон:Convert of travel. A swinging arm was used on the rear with twin non-adjustable shock absorbers. The top of the shock absorbers could be attached in four different positions to adjust the rear suspension geometry.Шаблон:Sfn 3-way adjustable shocks were fitted from 1972.Шаблон:Sfn
Brakes were Шаблон:Convert diameter drums front and rear, the front being the same as the unit used on the Monza Junior.Шаблон:Sfn Wire wheels were fitted with Borrani alloy rims,Шаблон:Sfn and 400x21 front and 300x18 rear tyres.Шаблон:Sfn
350 R/T
A few 350 R/Ts were produced in 1971 and were fitted with the 350 desmo engine.Шаблон:Sfn In 1974 the R/T was available in the domestic Italian home market fitted with the non-demo engine of the Mark 3.Шаблон:SfnШаблон:Sfn
References
Bibliography
- Шаблон:Cite magazine
- Шаблон:Cite magazine
- Шаблон:Cite web
- Шаблон:Cite book
- Шаблон:Cite book
- Шаблон:Cite book
- Шаблон:Cite web
- Шаблон:Cite book
- Шаблон:Cite web
- Шаблон:Cite web
- Шаблон:Cite web
- Шаблон:Cite magazine
- Шаблон:Cite web
External links
Шаблон:Commons category Шаблон:YouTube
