SPAN­ISH FLYER

BUL­TACO ME­TRALLA MK2 TT RACER

Old Bike Australasia - - BULTACO METRALLA MK2 TT - Story John Somerville Pho­tos John Somerville and Jim Scaysbrook

The ap­pear­ance of the Bul­taco Me­tralla Mk2 in 1966 her­alded a new level of per­for­mance and han­dling in a stan­dard 250cc road bike that was avail­able to the gen­eral pub­lic – or at least to “those in the know” about this rel­a­tively rare ma­chine: only 5,508 were ever made, com­pared to the mil­lions of their Ja­panese op­po­si­tion.

De­vel­oped from the ear­lier air-cooled TSS road rac­ers, the Me­tralla Mk2 was con­sid­ered by many to be the fastest 250cc stan­dard road bike in the World in 1966 – 67, listed at 103mph. This was cer­tainly achiev­able, but the bike had to be in per­fect tune, a cool over­cast day, a long straight stretch of road and a jockey-sized rider ly­ing down on the tank! It was only a mat­ter of time be­fore race kits (called “Kit Amer­ica”, as they were orig­i­nally de­signed for the Amer­i­can mar­ket) and fully race kit­ted bikes be­came avail­able for pro­duc­tion/club­man rac­ing, with many suc­cesses achieved world wide.

Bul­taco firstly made a hand full of spe­cial fac­tory Me­tralla Mk2 race kit­ted bikes in 1966-67 for se­lected rid­ers and events; th­ese are the Holy Grail for any keen Me­tralla en­thu­si­ast. In 2001 I was very for­tu­nate to find one of th­ese spe­cial bikes in Wan­garatta, Vic­to­ria where it had been hid­den for 15 years or so, lan­guish­ing in a garage, apart from an out­ing at Phillip Is­land. Lit­tle did I re­alise I would be un­ex­pect­edly of­fered the chance to buy the bike by the owner Ken Lucas. So af­ter sell­ing my soul I am now the proud owner of a very rare and spe­cial piece of Bul­taco rac­ing his­tory – the bike was raced by Tommy Robb into sec­ond place in the 1967 Isle of Man 250cc Pro­duc­tion TT. Bul­ta­cos also came first, rid­den by Bill Smith and sixth, rid­den by Aussie Kevin Cass. The shat­ter­ing per­for­mance of th­ese

bikes as­tounded the mo­tor­cy­cle fra­ter­nity, Bill Smith’s race time was 1 hour 16 min­utes 38.2 sec­onds (av­er­ag­ing 88.63mph / 142.64kph), with Tommy Robb just 0.4 sec­onds slower: fast enough for them to place third and fourth in the 500cc Pro­duc­tion race and sixth and sev­enth in the 750cc Pro­duc­tion race! Bill Smith’s lap record stood un­til 1974 when it was fi­nally beaten by resur­fac­ing of the track, mod­ern race tyres and new en­gine tech­nol­ogy. Tommy’s bike also came fourth in the 1968 250cc Pro­duc­tion TT, rid­den by Brian Richards who bought the bike through Bill Smith af­ter the 1967 TT and who sold the bike to Kenny Lucas in 1980s. The Bul­taco’s TT win was very con­tro­ver­sial, many thought that they were “cheat­ing” us­ing spe­cial fac­tory bikes equipped with un-muf­fled ex­pan­sion cham­bers. How­ever, all the race kit parts were listed as op­tional ex­tras in the stan­dard road bike parts cat­a­logue so they were le­gal – even the in­cred­i­bly loud ex­pan­sion cham­ber! In those days there were no noise lim­its on road/race bikes, in fact there was no way of ac­cu­rately mea­sur­ing the sound level. The race rules at TT Pro­duc­tion bikes stated that “bikes had to be fit­ted with an ef­fi­cient ex­haust sys­tem”, and there is noth­ing more ef­fi­cient than an ex­pan­sion cham­ber! The rac­ing kit was summed up in a fac­tory brochure: “the kit can be eas­ily in­stalled by the cus­tomer him­self, all that is re­quired is a set of span­ners, a medium cut file, a drilling ma­chine, three drills and a dose of en­thu­si­asm”. It cost about half the price of a stan­dard new Me­tralla and con­sisted of a spe­cial fi­bre­glass race tank with mount­ing brack­ets, a steel 2-piece ad­justable hump-backed sin­gle seat, a sil­ver bikini fair­ing, clipons, rear-sets, rear brake switch mount, ported bar­rel (same as the Pur­sang Mk2 moto-crosser), 11:1 or 12:1 high com­pres­sion head, mod­i­fied pis­ton, a close ra­tio gear­box, as­sorted drive sprock­ets, ex­pan­sion cham­ber, car­bu­ret­tor bell­mouth and jets, ca­bles, a FEMSA elec­tronic ig­ni­tion sys­tem and even a rac­ing spark plug. Com­plete race-kit­ted bikes could also be pur­chased di­rectly from the var­i­ous Bul­taco deal­ers. This bike was meant to be raced, so I have set about fix­ing it up to race in the Aus­tralian Post-Clas­sic scene to see how well it goes, be­fore re­tir­ing it. The bike is a lit­tle dif­fer­ent to when it raced in 1967 due to race dam­age, wear and tear etc. over the fol­low­ing 20 years but the main parts of it are still orig­i­nal. I fit­ted a larger 36mm Amal Mk2 con­cen­tric carb in place of the 34mm Amal Mk1 that came with the bike which have a bad rep­u­ta­tion for break­ing slides and de­stroy­ing pis­tons. There is also a lot of in­for­ma­tion around re jet­ting the 36mm Mk2, which I de­cided to run on 100 oc­tane petrol rather than al­co­hol, with syn­thetic rac­ing oil at 25:1. The gear­ing and ig­ni­tion were checked, start­ing was hard, first gear seemed very high but once un­der way the bike seemed to run O.K. A very firm front sus­pen­sion was traced to the right hand fork leg stick­ing on the stan­chion, but a re­place­ment fork leg fixed this. The front brake back­ing plate was also re­placed due to a very loose brake shoe pivot pin and the brake pads ra­dius ground to match the iron liner. The front wheel rim had also been laced up with an in­cor­rect off­set, re­sult­ing in the wheel be­ing off cen­tre.

A faulty top coil stopped pro­ceed­ings at our first race meet­ing at Syd­ney’s Eastern Creek in Fe­bru­ary 2002. The next race meet­ing was at Syd­ney’s Oran Park in April 2002 which was a bit more suc­cess­ful than the one at Eastern Creek, at least it started

and fin­ished it’s only race – but it had a mys­te­ri­ous “miss” in the en­gine. Three dif­fer­ent ig­ni­tions and two dif­fer­ent carbs? It can’t be ig­ni­tion or car­bu­ra­tion – but what else can it be? Af­ter a thor­ough clean out of the fuel tank and fuel I took it out onto the high­way and turned up the wick – but it was still “miss­ing”! A strange sort of “miss” though, as it only did it in 3rd gear (both un­der load and not) and any­where be­tween medium to high revs. I de­duced that the only thing it can pos­si­bly be, by a process of elim­i­na­tion, is a gear­box prob­lem, 3rd gear is mo­men­tar­ily slip­ping out of gear then back in, so quickly that it feels like an ig­ni­tion prob­lem, there is no time for the revs to peak like when a bike nor­mally jumps out of gear. The en­gine was re­moved from the bike and stripped down, and to my hor­ror, the sleeve gear on the main shaft ap­peared to be the same as a Pur­sang moto-crosser – one tooth more than a stan­dard Me­tralla Mk2 race kit cog. A quick count of the teeth on some of the other main-shaft gears pro­duced the same re­sult: they were not stan­dard Me­tralla race kit ei­ther! My stom­ach sank, it ap­peared that it may not be the cor­rect race kit gear­box; did this mean that a Pur­sang gear­box was fit­ted in­stead? Maybe the whole en­gine was sim­ply a Pur­sang “ring-in”? I had vi­sions of all the $ I paid for this “spe­cial” bike be­ing wasted! In short, ev­ery cog in the gear­box was dif­fer­ent to any other 5-speed cog that Bul­taco had ever made. It was a spe­cial fac­tory gear box af­ter all, con­firmed by cal­cu­lat­ing the over­all ra­tios which turned out to be al­most iden­ti­cal to the stan­dard race kit gear­box, just a tiny bit higher. I felt very re­lieved, the bike was in­deed a gen­uine fac­tory racer, one of only a hand full made. A new 3rd gear se­lec­tor fork and a “silk shift” mod­i­fied se­lec­tor drum were bought and I made a new lay shaft spacer. While the en­gine was apart I had the pis­ton skirt te­flon coated and the crown ce­ramic coated, by High Per­for­mance Coat­ings in Melbourne. The “miss” in the en­gine had been elim­i­nated, the en­gine runs as smooth as silk in all gears at all speeds. The bike com­pleted its next meet­ing at Eastern Creek in 2003, so now that the bike had been suc­cess­fully raced I could re­tire it and re­store it to its for­mer glory as raced at the Isle of Man. I had an un­ex­pected but very wel­come visit in March 2003 from Harry Lind­say, the orig­i­nal Bul­taco im­porter into Ire­land in the 1960s and the first owner of my bike. He flew over to Aus­tralia for a few days to visit friends, in­clud­ing Aussie racer Kevin Cass who raced one of Harry’s Me­tral­las in the 1967 Pro­duc­tion TT, com­ing sixth af­ter be­ing plagued with en­gine prob­lems. We spent a very pleas­ant cou­ple of hours talk­ing Bul­ta­cos and “the old days”. In early 2004 I con­tacted Tommy Robb and Bill Smith in the UK to see if they had any

in­for­ma­tion or pho­tos of my bike. Tommy sent me a signed photo of his bike rac­ing in the TT, Bill Smith con­firmed that my bike is in­deed one of the three 1967 IOM 250cc Pro­duc­tion TT bikes. My plans to re­store the bike were side­lined in 2003 when I took up rac­ing VMX in the NSW HEAVEN se­ries, and rac­ing kept me busy for the next few years un­til my body cried enough! I ob­tained all the gen­uine parts and in­for­ma­tion I needed to fully re­store the bike as it was raced at the 1967 IOM TT. I started the restora­tion in earnest in mid-2016 so the bike could be fin­ished by June 2017 – the 50th an­niver­sary of its 1967 IOM suc­cess. The first task was to make a new ex­pan­sion cham­ber (us­ing stan­dard Me­tralla race kit specs), mod­i­fied to tuck in un­der the en­gine as per pho­tos of the orig­i­nal bike. I made a new tank strap, race stand, rear sprocket cover, tacho mount, front tank mount­ing bracket and fixed the orig­i­nal steel race kit seat base, made a cush­ion and had it pro­fes­sion­ally cov­ered with black leather – rough side out­wards. The frame, swing arm, triple clamps, rear brake torque arm, head­light shell and foot brake lever were stripped down, bead blasted and painted gloss black (one coat of rust proof enamel straight onto the bare steel, as per the orig­i­nal). The wheels were stripped down, the steel spokes were cleaned up and re-zinc plated (the orig­i­nal fin­ish), the hubs bead blasted, pol­ished and the ribs around the out­side painted satin black. The orig­i­nal nickel plated brass spoke nip­ples were still good so I re-used them. New wheel bear­ings and seals were fit­ted. A pair of old Dunlop “tri­an­gu­lar” race tyres were fit­ted as th­ese were used in the TT, a 2.75 x 18 front and a 300 x 18 rear. Th­ese are for display only, as I plan to build a spare pair of wheels fit­ted with mod­ern tyres so I can safely ride the bike on the street. Mean­while I had all the chroming and zinc plat­ing done and re­stored the front forks, fit­ting new fork oil seals and valves in the damper rods and re­fill­ing the forks with 85cc of ~30 weight hy­draulic oil. The Gir­ling shocks were re­built and filled with 5 weight fork oil, they now work per­fectly.

“A pair of old Dunlop ‘tri­an­gu­lar’ race tyres were fit­ted as th­ese were used in the TT...”

The rest of the restora­tion fol­lowed nor­mal pro­ce­dures, then lastly restor­ing and painting the steel mud­guards and fi­bre­glass tank (which I sealed in­side with epoxy resin to proof it against the nas­ties in the mod­ern fu­els). I fol­lowed the fac­tory parts book to en­sure that all the parts I used were cor­rect and wher­ever pos­si­ble orig­i­nal or gen­uine NOS– right down to the “Bul­taco” headed bolts, anti vi­bra­tion wash­ers and rub­ber hand­grips, gear lever and carb top rub­bers and con­trol ca­bles. But I did use Loc­tite prod­ucts to en­sure parts did not vi­brate loose! A wir­ing har­ness was made up us­ing the cor­rect size and colour wires pushed through “spaghetti” tub­ing. The wir­ing was mod­i­fied from the stan­dard road­ster har­ness as no rear brake light, switch or re­sister were fit­ted; the head­light, tail light and horn are fit­ted and work, as per pro­duc­tion rac­ing reg­u­la­tions. The colours of the rac­ing plates and num­bers are strange. Dur­ing the TT the oval front plate on the bikini fair­ing was painted white, with black num­bers, the two oval plates on each side of the bike (where the road­ster tool boxes would nor­mally go) were red, with white num­bers. To com­pli­cate mat­ters, there are pho­tos of the bike taken some­time af­ter the race show­ing a red front plate with white num­bers, to match the side plates! In th­ese ‘pho­tos the Gir­ling shocks have also been tem­po­rar­ily re­placed with stan­dard Be­tors – but who knows why? The end re­sult is a bike that I am proud to own and which takes pride of place in my col­lec­tion of Me­tral­las. I plan to give it the oc­ca­sional out­ing at se­lected rally events, be­gin­ning with the Deben­ham Rally at Moss Vale in June 2017, which is where the pho­to­graphs you see here were taken.

Now, if only I can find Bill Smith’s win­ning bike!

TOP LEFT Tommy Robb heads for sec­ond place in the 1967 TT. TOP RIGHT 250cc Pro­duc­tion TT win­ner Bill Smith. ABOVE Robb rounds Quar­ter Bridge dur­ing the Pro­duc­tion TT.

The Me­tralla duo at the 2017 Deben­ham Rally in the NSW South­ern High­lands. John Somerville’s well-trav­elled model (left) and An­drew Flow­ers’ race-kit­ted ver­sion.

Fac­tory race kit com­po­nents.

An­drew Flow­ers’ me­tralla which is fit­ted with the cus­tomer race kit. The power depart­ment of An­drew’s bike, with MkII Amal Con­cen­tric fit­ted. An­drew Flow­ers giv­ing his Me­tralla a dose of coun­try air.

Rear chain which runs in a sealed case with snail cam ad­justers. Ex­tra looped bracket to hold the footrest and ex­haust pipe dis­tin­guishes the TT frame.

Tacho drive is taken from left side crank. The “ef­fi­cient ex­haust sys­tem”. Orig­i­nal-spec Amal Monoblock carb with its rub­ber cap.

ABOVE Works fuel tank is higher than the Bul­taco race-kit ver­sion. ABOVE RIGHT ‘In­side out’ leather seat. RIGHT Switchgear; that’s it. FAR RIGHT Au­then­tic Bul­ta­co­headed bolts through­out. BE­LOW RIGHT Cock­pit view. FOOT­NOTE: This story is edited from John Somerville’s book, “Bul­taco – Mi Ob­se­sion”, copies of which are avail­able form Bul­taco Parts Aus­tralia at Toongab­bie, Vic­to­ria. Un­der­go­ing restora­tion RIGHT Light and func­tional – the su­perb front brake. BOT­TOM LEFT Gir­ling rear shocks re­placed stan­dard Be­tor. BOT­TOM RIGHT Front cowl­ing with its con­tro­ver­sial num­ber plate – should it be red? in the work­shop.

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