Nor­ton 88 A civ­i­lized twin

For those of us who can re­mem­ber back that far, the of­fi­cial com­ing-of-age cel­e­bra­tion rep­re­sented by the 21st birth­day party can be a trea­sured oc­ca­sion, an after­wards indis­tinct tale of ex­cesses, of gifts, of well-wish­ing.

Old Bike Australasia - - CONTENTS - Story and pho­tos Jim Scays­brook

So what did Tony do with his lus­cious gift? Leap aboard and ride it far and wide? Pose at the milk bar? Plant a femme fa­tale upon the pil­lion to the envy of his mates? No. “I rode the bike for about 500 miles, and be­ing ac­cus­tomed to Ja­panese ma­chin­ery was thor­oughly unim­pressed by the level of vi­bra­tion as it shed parts down the road on every out­ing,” re­calls Tony. “This in­cluded both muf­flers, the head­lamp and even the gen­er­a­tor at one time. The source of this vi­bra­tion was traced – many years later – to loose and even miss­ing en­gine bolts.” So he pulled it apart and shoved the com­po­nents in boxes, there to re­main un­til 2016. Had it not been for the ex­per­tise and per­se­ver­ance of Don Tonkin, McLaren Vale’s crafts­man par ex­cel­lence, the 88 may well still be in those boxes.

At this point, it’s worth a quick run­down on the Model 88 it­self, be­gin­ning with the grand­daddy of all the Nor­ton par­al­lel twins, the Model 7, which set fans talk­ing when it made its pub­lic de­but at the Earls Court Mo­tor­cy­cle Show in Novem­ber 1948. The all­new en­gine which pro­duced 29hp was the work of the cel­e­brated en­gi­neer Bert Hopwood, who had a fair hand in the con­cepts of both the Tri­umph twin and the Ariel Square Four and would later be re­spon­si­ble for the BSA A10 twin. Most of the Model 7 run­ning gear was sourced from ex­ist­ing Nor­ton stock, mainly the sin­gle cylin­der ES2, along with a beefed up Nor­ton gear­box. That gear­box ac­tu­ally be­gan life around 1931 as a Sturmey-Archer prod­uct, but when their pro­duc­tion ceased, Nor­ton picked up the de­sign and had it pro­duced for their use by Bur­man. The Hopwood de­sign was ac­tu­ally Nor­ton’s sec­ond at­tempt at a par­al­lel twin, fol­low­ing an ex­er­cise in 1946 by Jack Moore. This pro­to­type, which was also fit­ted into an ES2 frame with plunger rear sus­pen­sion and two-way-damped Nor­ton Road­holder forks, was sim­i­lar to the Tri­umph, with two camshafts and two sep­a­rate rocker boxes cast in light al­loy. When Hopwood came on board at Nor­ton in 1947, he ex­pressed lit­tle in­ter­est in the Moore de­sign and started with a clean sheet of pa­per. Like its Bri­tish con­tem­po­raries, the new en­gine used a 360-de­gree crank­shaft, with its in­her­ent vi­bra­tions. This trait was not seen as a ma­jor is­sue in the fairly mild state of tune of the Model 7, but cer­tainly be­came one as larger ca­pac­ity ver­sions came on stream, each pro­duc­ing more and more power. The vi­bra­tion bug­bear reached its nadir with the 750cc At­las, and led di­rectly to the Com­mando con­cept which iso­lated (not elim­i­nated) the vibes via the Iso­las­tic frame/en­gine mount­ing sys­tem. The orig­i­nal 497cc en­gine, with bore and stroke of 66mm x, used cast iron for the head and block, with a sin­gle car­bu­ret­tor and the fairly ubiq­ui­tous Lu­cas mag­neto and dy­namo. A com­bi­na­tion of gears and chain drove the sin­gle camshaft at the front of the en­gine, and a fi­bre gear run­ning off the camshaft in turn drove the dy­namo. The built-up crank­shaft, with a cen­tral cast iron fly­wheel, was sup­ported by two main bear­ings; a ball race on the tim­ing side and a roller race on the drive, which in­cor­po­rated an outer oil seal. Ex­haust ports were splayed to al­low max­i­mum cool­ing air to reach the area, the air then directed through the hot­ter ar­eas of the en­gine. The Model 7 was a solid, if un­re­mark­able ma­chine, but in 1952 came a change that was to in­voke the Nor­ton twin with a com­pletely new per­son­al­ity, although the Model 7 con­tin­ued in pro­duc­tion for a pe­riod. The ‘Feath­erbed’ frame that had graced the works Nor­ton rac­ers for two years ap­peared wrapped around the twin en­gine at the 1951 Earls Court Show, where it caused much ex­cite­ment. The Model 88 Dom­i­na­tor had been born. How­ever for the home mar­ket it was only a fleet­ing glimpse, as the 88 was orig­i­nally listed for ex­port only. The frame fol­lowed the same gen­eral lay­out as on the Manx, but was made from a lower grade Reynolds tub­ing, arc

welded rather than bronze welded, with the rear swing­ing arm piv­ot­ing on Si­lent­bloc bushes. As on the Manx, the rear sub-frame was bolted on and con­trolled by Arm­strong spring and damper units. Up front were new, shorter Road­holder forks mod­elled on the Manx jobs, with the steer­ing crowns now run­ning in ball bear­ings rather than cups and cones. The Model 88 tipped the scales a full 40 pounds (18kg) lighter than the Model 7. Like the Manx, the 3.5 gal­lon petrol tank on the 88 sat on rub­ber pads on the top tubes of the frame and was held in place by a strap which hinged from the front, be­hind the steer­ing head. Nat­u­rally, few fit­tings or chas­sis com­po­nents car­ried over from the Model 7. Un­der the dual seat that re­placed the Model 7’s sprung sad­dle sat a tool tray, with the oil tank and bat­tery be­low that, both of these sit­ting on a plat­form above the gear­box. Brakes re­mained at 7-inch but the front wheel was now 19 inch with a 3.25 sec­tion tyre. The Show model 88 had a black frame, but by the time the 88 went on sale in the UK, all metal parts in­clud­ing the frame were painted in a metal­lic grey. The petrol tank was chrome plated with grey pan­els with black and red strip­ing, as were the wheel rims. This dé­cor was not uni­ver­sally pop­u­lar, at least with the Bri­tish, so for 1953 a black and sil­ver op­tion was listed. The peashooter si­lencers used on the Model 7 gave way to a new el­lip­ti­cal shape, with the in­let at the bot­tom and the out­let at the top. These soon gained the nick-name of ‘pear-shaped’ si­lencers. For 1958, the Model 88 re­ceived an 8-inch front brake, an item it sorely needed, as stop­ping power, or lack of it, had been a uni­ver­sal crit­i­cism, but the ma­jor change in the twin’s de­sign came the fol­low­ing year when a new light-al­loy cylin­der head was fit­ted, along with an Amal Monobloc car­bu­ret­tor to re­place the old Amal 6 Type. The Feath­erbed frame fi­nally be­came a one-piece unit, with the sub-frame welded in place rather than bolted on. The sin­gle-sided hubs were also scrapped in favour of cast al­loy full-width hubs.

In its pri­mary ex­port mar­ket, the United States, the 88 sold well but there was a grow­ing clam­our for more power. Both Tri­umph and BSA had al­ready an­swered this de­mand, with the 6T (Thun­der­bird) and A10 (Golden Flash) re­spec­tively. Nor­ton’s an­swer was the Model 99, with the ca­pac­ity stretched to 596cc (68mm bore x 82mm stroke), with a slightly larger 1 1/16” car­bu­ret­tor. How­ever the Model 88 con­tin­ued in pro­duc­tion, as it would un­til 1966 (as the 88SS), with an in­crease in com­pres­sion ra­tio to 7.8:1. Both mod­els had their midriff ti­died up, with a new oil tank on the right and a bat­tery cabi­net on the left. 1956 also marked the end for the ven­er­a­ble Nor­ton ‘lay-down’ gear­box, with the cas­ing re­vised and now man­u­fac­tured by Nor­ton’s owner AMC in Lon­don. De­tail changes con­tin­ued to be made to the 88 and 99 year by year, such as Gir­ling rear units in 1957 with a Lu­cas RM15 al­ter­na­tor, coil ig­ni­tion and dis­trib­u­tor re­plac­ing the mag­neto in 1958.

In an ex­er­cise that gen­er­ated a ton of pub­lic­ity, for­mer World Side­car Cham­pion Eric Oliver took a vir­tu­ally stan­dard Model 88, fit­ted a Wat­so­nian Monaco side­car, and fin­ished an amaz­ing tenth (with Mrs Pat Wise in the chair) in the 1958 Isle of Man Side­car TT. As the new decade loomed, Nor­ton em­barked on a restyling ad­ven­ture with the ad­di­tion of a rear en­clo­sure sim­i­lar to Tri­umph’s unloved ‘Bath­tub’, which was fit­ted to both the twins as a De Luxe ver­sion, but which only lasted two years in pro­duc­tion. 1960 also saw the ad­di­tion of what be­came known as the ‘Slim Line’ frame, with the top frame rails moved closer to­gether, along with a dif­fer­ent style petrol tank with cast metal badges. The 88 also re­ceived mod­i­fied port­ing and slightly higher 8.0:1 pis­tons. The 88SS (Sports Spe­cial) came on steam for 1961, with twin car­bu­ret­tors, high per­for­mance cams, dual valve springs, a fur­ther lift in com­pres­sion ra­tio and lighter pushrods, which pushed power up to 36hp at 7,000 rpm. To deal with the ex­tra poke, stronger clutch springs were fit­ted. Op­tional ex­tras on the 88SS in­cluded rear set footrests, a rev counter and sin­gle muf­fler, and a Si­amesed ex­haust sys­tem. The last of the stan­dard Model 88s were built un­til the end of 1963, the 500 con­tin­u­ing only as the 88SS, which fi­nally re­ceived 12 volt electrics in 1964. And af­ter 14 years in pro­duc­tion, the 88 came to an end late in 1966.

The res­ur­rec­tion

Don Tonkin’s restora­tion of Tony Moris­set’s Model 88 is well-nigh flaw­less and typ­i­cal of this mas­ter crafts­man’s work and at­ten­tion to de­tail. Don says there are ac­tu­ally two shades of the Nor­ton Poly­chro­matic Grey, and this is the lighter of the two, which he matched from the orig­i­nal colour on the in­side of the tool case. The ac­tual paint­ing was done by Daniel Stone, and the plat­ing by A Class Chrome in Ade­laide. Be­ing a 1955 model, Tony’s 88 still has the “lay­down” Nor­ton gear­box, with mag­neto ig­ni­tion, and fea­tures the cir­cu­lar plas­tic tank badges in­tro­duced for that model year. The new-for-55 al­loy cylin­der head sits atop the iron block. The pri­mary chain case is also the pressed steel type with the outer cover re­tained by a cen­tral fix­ing that also mounts the left side footrest.

The at­ten­tion to de­tail car­ries through to the be­spoke bat­tery case made by Don from wood, which is hol­low and con­tains a modern unit. Sit­ting un­ob­tru­sively un­der the seat on the side of the tool tray is the ig­ni­tion kill switch, as there is no key for the mag­neto ig­ni­tion. De­spite its age, but per­haps be­cause of its ex­tended pe­riod of hi­ber­na­tion, the 88 re­tains the orig­i­nal Arm­strong rear shock ab­sorbers, which are one-size-fits-all and de­void of any spring­ing or damp­ing ad­just­ment. The wheels were re­built with rims and spokes sourced from Cen­tral Wheel Com­po­nents in UK.

This was no cos­metic restora­tion, as the old Nor­ton, as well as be­ing com­pletely dis­man­tled and suf­fer­ing the in­evitable rav­ages of life in a loft, was pretty tired to be­gin with. “The bike had a high mileage on it, as con­sid­er­able wear in all en­gine com­po­nents, bushes and even fork legs was ev­i­dent,” says Tony. “The new seat, and the muf­flers and header pipes, were pur­chased from Norvil in UK, and Burlen Fuel Sys­tems, also in UK, sup­plied the cor­rect Amal Monobloc carb, al­ready jet­ted for the model. In­stead of fit­ting a modern belt pri­mary drive and clutch, we de­cided to re­build the orig­i­nal Nor­ton com­po­nents. Fric­tion ma­te­rial is modern “Sur­flex” rather than cork. The ny­lon-lined ca­bles and cor­rect-pat­tern levers make the clutch light and re­spon­sive. The op­tion to con­vert to a belt drive at a later date is al­ways avail­able as these are an off-the-shelf con­ver­sion from Norvil. The me­chan­i­cal Lu­cas volt­age reg­u­la­tor was re­placed with a 60volt solid state item from Groves in the UK. This is fit­ted in­side the Lu­cas hous­ing and wired to the orig­i­nal ter­mi­nals.” When I pho­tographed the bike, the beau­ti­fully re­built Nor­ton had just 8 miles on the odome­ter, but this will change, be­cause Tony had a group of very keen mates in the McLaren Vale re­gion, all of whom need lit­tle prompt­ing to get out and en­joy the won­der roads in the area. And one thing’s for sure, thanks largely to Don Tonkin, the Model 88 is in far bet­ter fet­tle than it was when Tony rat­tled to a halt and parked it up all those years ago.

One touch of this but­ton and the horn will have mis­cre­ants scut­tling in ter­ror. Chrome –sided petrol tank was done lo­cally in Ade­laide.

RIGHT 7-inch rear brake has a pressed steel back­ing plate. BE­LOW RIGHT Stan­dard Lu­cas tail light graced many Bri­tish bikes of the time.

The ven­er­a­ble Nor­ton twin in its orig­i­nal 497cc ca­pac­ity, matched to the Nor­ton ‘lay­down’ gear­box. En­gine num­ber iden­ti­fies 1955 pro­duc­tion. Orig­i­nal 1-inch Amal Monobloc carb.

ABOVE LEFT Nor­ton pressed steel pri­mary chain cases are no­to­ri­ous for leak­ing, but this one doesn’t. ABOVE Mag­neto con­tains modern en­hance­ments. LEFT Muf­flers re­tained the shape of the orig­i­nal Model 7 but were re­placed with more modern look­ing ver­sions in 1956.

Ter­ri­bly Bri­tish in­stru­ment fas­cia. Small park­ing light sits be­low the head­light. Two-way damped Road­holder forks – state of the art.

ABOVE Eric Oliver gives Mrs Pat Wise the ride of her life in the 1958 Side­car TT. ABOVE Hand made replica bat­tery box con­tains modern in­ter­nals. BE­LOW Cut out switch nes­tles un­der the seat.

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