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~~~~~L_ASS~C~~~-AU_'_u_M_N _1~-~-~-~-s~~-g Suzuki RGSOO L:=:=:=~=====:::'.:::::'.:======------ A decade at ·the top .... DOMIRACER lnfullflight. Tom Phi/lis on his way to third place in the 1961 Senior TT, having lapped at over lOOmph. Doug Hele who an uprated the Manx new The thought of a Norton and who 500cc Dominator twin was responsible in 1948, the famous 5 OOcc twin cylinder for the Domiracer Birmingham factory also of 1961. stated that it was designed on/y as a racing bike to replace docile touring machine and was not the beloved Manx sin suitable for racing. But the very name ' Norton' meant gle was not a popular racing and the post-war export market to the United States wanted a 500cc twin move by the Norton from Norton, based on a standard design, that could win factory - the purists at Daytona, America's didn 't like the idea of equivalent to the a race bike based on a Isle of Man TT. boost sales, badgered the Birmingham factory for However, even thi s rel ativ e success An earlier indication that demand also If racing suc roadster. The But for road racing, then centred on race bikes suitable for their racing rules. fa il ed to lea d to more twins being pro existed at home for a racing version of cess ever helped Europe, Norton continued to rely on ohc As a result, two mildly-tweaked duced, even for the cagcr US market. It the 500 Dominator twin was the entry of to sel! motorcy 'Domiracer' was singles, especially after the 'featherbed' Dominator twins were sent to Daytona, didn ' t hclp the cause of the twin that one two private bikes in the 1951 Manx cl es, Norton frame was introduced in 1950. The post one of which did well to finish third in of a pair provid ed for marshals at the Grand Prix. Little is known of these Motors Ltd held developed however war 'International ' roadsters were pro 1953. Manx brokc cl own. machines, except that both finished, the ace, for they duced in only small numbers and were dominated and could have had di scontinued after 1956. Facto1y picture of Daytona from lndeed, even the successes of Geoff the Do111irn cer. 1949 until 1952 more success had the Duke ( 1950-52) did little to sell Norton with 500cc factory survived, machin es in America, where the feath overhead erbed frame was also initially banned. camshaft single writes Charlie Rous. cylinder ' Manx' HE ohv vertical twin designed by models fitted Bert Hopwood in 1947 was entire with kick AMA 750cc sicl e va lve l lurlcy-Davidson Tly new, but the frame of the first starters. They and Indian opposition. Dominator, the Mode! 7, was essentially ~ were certainly The main point of thi s was that under pre-war, with plunger rear springing. not ' Internat AMA regulations, ail machines had to be Subsequent development brought the ional' roadsters, based on a standard design and not pro adoption of the featherbed frame in as the regula duced specifically for racing. This was 1951 , but the engine remained essential tions stipulated. the AMA's argument against the Manx ly unchanged for 25 years - even when After this Norton. They would not accept, quite enlarged to 600, 650, 750 and finally four-year run of wrongly, that the production Manx 850cc. success, the mode! was derived from the original The AMA's racing restrictions -intro American 'International' roadster. duced in 1953 did much to boost Motorcycle Even so, if Norton did not break the demand for British sporting motorcycles lt looked like an Association changed its rules and rules, they certainly bent them. In the in the United States, but BSA and ordinary banned al! overhead camshaft engined event, British vertical twins, led by Triumph gained most of the resulting Dominator • but machines. But 500cc ohv (push rod) Triumph, were in great demand and extra sales. oh! the difference ! engines, singles or twins, remained eligi Norton's American agents wanted a sim This did not please Norton's north ble to compete against the traditional ilar twin that could win races and help to American agents who understandably 48 CLASSIC RACER CLASSIC RACER 49 DOMIRACER NORTON'S RACING TWIN Tom Phillis gets the Visitors Trophy afterthe 19611T Francis Bearl 1h1rr y Bent 55th and John Waite 64th! se ries. built this version Wc can only presume that the bikes of the Do111imcer wcrc vi1tually standard models produc for a priva te c11 s i ng j ust 29 .5 hp. tonze1· al af111osl erious thought was only given to the sa111 e li111 0 ns Dominator engine development after the fa clo1J> Doug Hele joined Norton from Do111iroc11r Douglas in 1956. His brief was to appea r11 rl. W11s develop a replacement for the 500cc there a 11y co11 11 ec Manx from the ohv twin to meet tio11 ? American racing requirements. So, with this AMA priority in mind, Doug set about this demanding task. Astonishingly, the entire project was kept secret for the next four years ! This was not particularly difficult, as whenever a ' lively' Dominator appeared, it was invariably assumed to be an enlarged 600 or 650cc development mode!. lt was not until many years later that Norton revealed that the eng in es used in the Dominator whi ch won th e 500cc class of the Thruxton 500 in 1960 and '61, were actually Domiracer prototypes. Norton finally admitted the existence mem of a racing twin at the Isle of Man TT in ories of the Grand 1961 when they also announced it as a Prix Triumph and 045 likely replacement for the ageing Manx. Matchless roadster-based twins which This latter announcement was not had proved fast but umeliable. Creg- well received. Despite the demand for a ny-Baa on his first new production racing machine, the HE Norton Domiracer didn't get practice lap. There was prospect of a Norton racer based on a off to a very bright start either. no serious damage to man or roadster dismayed the establishment. T First to ride it on the TT course machine and, minus fairing, Phil Many private entrants had expensive was Phil Read, and he dropped it at Tom Phiflis 011 th e Domirnce1· chases was able Pete1· Middleton's to ride o n to th e Manx No1·to11 pits where he admittcd th · li vc ly pow ·1· M • J 11 t I' through the noto of the twin had caused him 10 slid ·off. 11 11d !( 11d • 11 11 ! Jll Mu11 x rious Glen Helen Phil did not ride the D mira · ·r 11 g11!11 , Hl1q il' H. JlJiJlll H'H first la p was section in practice preferring hi s own Manx fo r th · rn " Il '!H.'1 3mph und hi s second 100.36mph, for the 1961 was also turned cl own by Mik e ltuil wood p1111 lng hl111 f'our th , o nl y 1.4 seconds averaged over lOOmph ifhe had not lost Senior TT. who, it was also revcalcd, had se rctl y dow 11 0 11 Mclnl yrc. IOOOrpm when tappet adjustment went tested the twin at Daytona a fcw 111 0111h s slack due to pushrod trouble. earlier. "Tl · · The 1961 TT engine incorporated Mike, who won the 196 1 Seni or 1ere IS no questwn many special parts - stiffer crank- TT on his own Bill Lacey tuned lh a l i r lhe 500 Domiracer had shaft with thicker big end jour- Manx Norton, told me after- · d · · ld h b nais, shorter con rods, nimonic wards that he did not even con- gonc 111 lO pr UCtJOil lt WOU ave een a valves, 11: 1 compression ratio, sider racing the Norton twin in w rthy successor to the Manx. steeper inlet ports and TT Amal preference as it was an W h d , · h b h h carburettors. Power output was unknown quantity, unproved and e a 111 engme on t e enc t at gave about 50bhp and this, combined possibly umeliable. 57 bhp" said Paul Dunstall with a Iower, Ieaner, Iighter by 35Ibs Australian Tom Phillis had no such ' chassis, made the production Domiracer doubts however. Eager for a works ride, project worth pursuing. he accepted Hele's offer of the twin He was eventually to finish third after This was confirmed when Phillis eagerly and after just two satisfactory Hocking dropped out, leaving Norton in raced the machine in the Ulster Grand practice laps he rode it in the race. the first three places. Afterwards, Phillis Prix, for with its ' lost' 1OOOrpm restored Phillis completed the opening lap in said he could have done better. He did to the 8000 maximum, he said he felt fifth place as Gary Hocking (MV) led at climb to second atone point in the race capable of challenging Hocking's MY. 102.62mph from Hailwood, Bob and was positive the twin could have That boast was to remain pure conjec- 50 CLASSIC RACER CLASSIC RACER 51 .. ·- DOMIRACER A Domiracer along side a standard Ma11X Norton. Note the saving in height and hence frontal area. turc, howcvcr, aft er Phillis came offïn the dard Dominator was purely coincidental. we t. They onl y looked alike, th e internais were Bcyond th at, the poss ibl e succcss of totall y diffcrcn t. th e Domiracer as a producti on ra c in g "Thcre is no question that if the 500 NORTON'S machine remained only an idea, for any Domiracer had gone into production it possibility of going into production ended would have been a worthy successor to when the Birmingham factory was closed the Manx.