NOR­TON SPACE­FRAME

The Space­frame Nor­ton of 1974 never lived up to the leg­endary ’73 Mono­coque, but it’s a ‘beau­ti­ful loser’ well worth pre­serv­ing, as this re­stored orig­i­nal proves

Classic Bike (UK) - - Contents -

The space­frame John Player Nor­ton racer re­placed the 1973 mono­coque, but JPN col­lec­tor Michael Braid ques­tions whether it was a bet­ter mo­tor­cy­cle

With its sleek fair­ings and nickel-plated net­work of frame tubes, the 1974 750cc John Player Nor­ton For­mula 750 racer is a thing of beauty. But the story of the Space­frame, as the ’74 Nor­ton has al­ways been known, is tinged with sad­ness. The Nor­ton team, stuck with the age­ing Com­mando twin en­gine, re­ally strug­gled to com­pete against the Ja­panese multi-cylin­der twostroke op­po­si­tion. Num­ber one rider and in­spired en­gi­neer Peter Wil­liams was never happy with the 1974 ma­chine and a crash in August of that year ended his rac­ing ca­reer and left him dis­abled.

Space­frames were built for the ’74 sea­son, to re­place the cel­e­brated Mono­coque raced in 1973. All five sur­vive: two owned by Joaquin Folch in Spain, an­other in Al­bert van der Hui­j­den’s Nor­ton mu­seum at Best in the Nether­lands and two in the UK. Of the two Uk-based bikes, one is owned by racer Rob Sewell, while the other – fea­tured here – has emerged from the West Lon­don work­shops of P&M Mo­tor­cy­cles in pris­tine track-ready con­di­tion. With 24/6/74 B stamped on its frame, it came up in a 2010 on­line auc­tion, when a stash of Nor­ton trea­sures were cleared out from a de­ceased Bel­gian dealer’s premises. Sur­rey-based John Player Nor­ton devo­tee Michael Braid ac­quired it jointly with New Yorker Jamie Waters, whose Nor­ton col­lec­tion in­cludes the only sur­viv­ing un­re­stored Mono­coque plus a Mono­coque replica by Nor­man White Rac­ing. The Bel­gian deal­er­ship in ques­tion, Mo­to­shop Pode­vyn, had prob­a­bly con­nected with the Nor­ton team when Wil­liams won a For­mula 750 race at Spa in 1974. Given their Space­frame af­ter the 1974 sea­son, Pode­vyn raced it briefly be­fore park­ing it for more than 30 years.

“It was cor­rod­ing from the bot­tom up, thanks to a damp floor,” Braid says. “The paint had been changed to slightly dif­fer­ent colours with­out the John Player lo­gos. The pri­mary chain was off, prob­a­bly to pre­vent unau­tho­rised start­ing, and the Krober revcounter was miss­ing, but other­wise it was com­plete.”

Braid is a re­tired wa­ter en­gi­neer who has worked as a con­sul­tant on Bond movie sets. In the late 1980s he bought the crum­pled frame of a 1973 John Player Nor­ton Mono­coque, which had been made into a stan­dard lamp and pre­sented to team rider Dave Crox­ford af­ter he crashed it spec­tac­u­larly at Sil­ver­stone in ’73. Richard Peck­ett at P&M had the job of turn­ing it back into a run­ning mo­tor­cy­cle. Mean­while, Braid was avidly col­lect­ing all the John Player team left­overs he could find and had a 1972-type tubu­lar-framed Player Nor­ton built by Nor­man White Rac­ing. He went back to Peck­ett for a ground-up Mono­coque build. Then, to com­plete the set, he com­mis­sioned recre­ations of not one but two Space­frames, one for him­self and one for Waters. They were al­ready well-ad­vanced when the orig­i­nal ar­rived at P&M in 2010.

Nor­ton’s rac­ing equipe, based at Thrux­ton cir­cuit, had a strong 1973 sea­son with the in­no­va­tive Mono­coque. It was the brain­child of rider/en­gi­neer Peter Wil­liams, who won a For­mula 750 TT and three out of six Transat­lantic rounds on it, while his team-mate Dave Crox­ford was Bri­tish 750cc Cham­pion. But for 1974, the stain­less steel Mono­coque was re­placed by a struc­ture of sim­i­lar

di­men­sions in short lengths of Reynolds 531 tub­ing. In mo­tor­cy­cling the space­frame idea, first seen on Ital­ian rac­ing cars, had been pi­o­neered by Moto Guzzi’s Grand Prix 350 in 1954 and the Nor­ton ver­sion pre­dated sim­i­lar struc­tures favoured by Bi­mota, Du­cati and KTM. Its cre­ators at Nor­ton’s Thrux­ton rac­ing HQ were fab­ri­ca­tor John Mclaren and welder Robin Clist. “It took us six weeks to make a Mono­coque, com­plete with ex­haust pipes, tanks and seat,” says Mclaren, who re­calls how his hands bled af­ter cut­ting up steel sheet with snips. “The only way we could do new frames for 1974 in the time we were given was to use tube. Robin made a jig and I sug­gested straight, rather than bent, tubes to save time. The only bends are on two top tubes.”

Sev­eral team mem­bers have dis­missed the sug­ges­tion that the change was to make the ma­chine more ac­ces­si­ble for me­chan­ics in the pad­dock. They in­clude Wil­liams, who was out-voted over ditch­ing the Mono­coque and dis­liked the Space­frame. His lap times on it were slower. Crox­ford, a care­free char­ac­ter not so in­tensely wrapped up in ma­chine de­vel­op­ment, had no prob­lem with the new frame, but strug­gled for re­sults against Kawasaki H2RS, Suzuki TR750S and the newly-ar­rived Yamaha TZ750. The team’s finest hour in 1974 was at a wet Hutchin­son 100 meet­ing, run anti-clock­wise at Brands Hatch. Wil­liams won the main event from Crox­ford, who again bet­tered the two-strokes to win the Evening News race. Their dark­est hour was the hor­rific crash at Oul­ton Park that ended pop­u­lar Peter’s rac­ing ca­reer. While the 1974 frame has an iden­ti­cal 56.5in (1422mm) wheel­base and 62° steer­ing head an­gle of its pre­de­ces­sor, Braid points out that the weight dis­tri­bu­tion is dif­fer­ent, with the en­gine shifted both for­ward and up­ward. “I don’t know why they did that,” he says. “The Mono­coque feels bet­ter bal­anced, even just push­ing it around. I think they fell down in get­ting rid of pan­nier fuel tanks. But they had to move on. We reckon the Space­frame is around 35lb (16kg) lighter.”

A Schrader valve on a frame tube un­der the seat on the right side is an in­ter­est­ing de­tail. Peck­ett ex­plains its func­tion: “Af­ter the tubes were pol­ished and bronze-welded to­gether, the whole as­sem­bly was pres­surised through the valve and sub­merged in

‘THE SPACE­FRAME IS AROUND 35LB LIGHTER THAN THE MONO­COQUE’

wa­ter to check for any pos­si­ble leak­ing from porous joints. Dur­ing plat­ing it would be put into a hot tank, when air would come out through any holes, then in a cold bath, when the chem­i­cals would be sucked in and cause cor­ro­sion.”

The rear sprocket is se­cured with a quick-re­lease threaded ring – a system of­ten seen on Amer­i­can dirt-track rac­ers – while the foldup footrests were there to com­ply with AMA reg­u­la­tions. A baf­fle be­neath the 33mm-bored Amal Con­cen­tric MKI car­bu­ret­tors de­flects air that has been warmed by the en­gine away from the in­takes, while the cylin­der and head finning is trimmed at the sides, a legacy of Mono­coque fit­ting.

Although Com­mando-based, the en­gine is of the short-stroke type (77 x 80.4mm) that Crox­ford used in 1974, which gave 84bhp on the Thrux­ton dy­namome­ter. Peck­ett re­placed aged steel con­nect­ing rods with new Car­rillo items, not­ing that this en­gine does not have the crank­shaft with a welded-on fly­wheel he saw in­side one of the two Folch-owned 1974 John Player Nor­tons. With more than 40 years of frame-mak­ing ex­pe­ri­ence, he is crit­i­cal of some as­pects of the Nor­ton team en­gi­neer­ing.

“It does look very nice, but in my view this frame is overde­signed and more rigid than it needs to be. And while it might not take as long as a Mono­coque to make, it still takes ages,” is his pro­fes­sional as­sess­ment. “They com­plained about not hav­ing enough power, yet they could have had more – they didn’t down­draught the car­bu­ret­tors and the bends in the ex­haust pipes close to the ports are far from ideal,” he adds.

The trans­mis­sion is car­ried over from 1973, with a Quaife fivespeed gear­box, a Wil­liams-de­signed dry clutch sup­ported by an outrig­ger bear­ing, a triplex pri­mary chain and an en­gine sprocket shock ab­sorber. Cy­cle parts sim­i­lar to the Mono­coque’s in­clude al­loy wheels, pi­o­neered by Wil­liams on his 1969 500cc Arter Match­less (see Clas­sic Bike August is­sue), with Lock­heed brakes dou­bled up at the front, mod­i­fied AJS mo­tocross forks and Koni rear shock ab­sorbers.

The en­tire com­bined tank and seat mould­ing con­tains fuel. The front filler is lower than the rear, so it is kept closed and a breather on its neck leads to a tube with its open end fixed higher than the rear filler. The repli­cas have sep­a­rate tanks and seats, also used in 1974. It is un­der­stood that Wil­liams’ Oul­ton crash was caused by a one-piece unit com­ing loose. On all three of the Braid/waters ma­chines, the front of the mould­ing is fixed to the top of the steer­ing head. An ear­lier 1974 method was to loop rub­ber bands over moulded-in hooks on each side, while the first Space­frame (one of the bikes now owned by Folch and dif­fer­ent from the other four) fea­tured bolted fix­ings.

The fair­ing was little al­tered from 1973, with side bulges to de­flect air around the han­dle­bars, echo­ing the Peel Moun­tain Mile fair­ing of the 1950s and 1960s. A new Krober revcounter has been fit­ted. Braid’s pre­served orig­i­nal fair­ing pat­terns

‘THE EN­GINE IS A COM­MANDO-BASED SHORT-STROKE’

helped to make the repli­cas ac­cu­rate – as did his cache of parts such as wheels, re­cently made by Creasey Cast­ings in Kent, who sup­ply the Peter Wil­liams Mo­tor­cy­cles new-build Mono­co­ques ven­ture (as seen in the May 2015 is­sue of Clas­sic Bike).

John Player’s three-year con­tract ended af­ter 1974 and much of the 1975 sea­son was wasted wait­ing for de­liv­ery of the dohc JA 750cc twin-cylin­der en­gine com­mis­sioned from Cos­worth En­gi­neer­ing. Ready for the last meet­ing of the sea­son, the JA/B twin was not the panacea the team and UK race fans had hoped for. It failed to live up to ex­pec­ta­tions and by the time the pro­to­type Nor­ton-cos­worth Chal­lenge model that it pow­ered was ready in the au­tumn, the main fac­tory in Wolver­hamp­ton had closed down. Nor­ton would not chal­lenge Ja­pan in rac­ing again for nearly 15 years, when Ro­taries from the Shen­stone fac­tory took to the track.

Now that Michael Braid has all three vari­a­tions of For­mula 750 John Player Nor­tons and has nearly fin­ished restor­ing the JPN team’s Dodge Dis­cov­erer trans­porter, he has a su­perb equipe to present at his­toric rac­ing events. And that’s not all – his two Cos­worths also await restora­tion at P&M...

This view be­neath the tank clearly shows the baf­fle that serves to de­flect warm air away from the car­bu­ret­tor in­take trum­pets

The re­stored 1974 Space­frame stands in front of P&M’S two clones Richard Peck­ett pre­pares to fire up one of his creations

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