CON­TIN­UED DEVEL­OP­MENT

Classic Racer - - MACHINE -

In that form the Mon­tjuic en­gine ini­tially pro­duced 67bhp at 9700rpm, run­ning on stan­dard F500 twin mega­phone ex­hausts and 36mm Dell’or­tos, but like most Ital­ian en­gines it seemed to like large carbs, and on­go­ing devel­op­ment saw 38mm units fit­ted for the 1984 sea­son. Be­fore that I gave it a cou­ple of shake­down races in the first-ever Bri­tish BOTT events run at the CRMC Don­ing­ton Park meet­ing in spring 1982. I made the top 10 both times, run­ning on Pirelli Phantom street tyres, but dis­cov­ered the en­gine was quite cammy. How­ever, the stan­dard six-speed gear­box re­solved any prob­lems this might have cre­ated, with its well-cho­sen ra­tios and su­perb shift ac­tion. Neu­tral was very hard to find, though, which meant I al­ways tried to be last back to the grid af­ter the warm-up lap. The clutch by the way was the stan­dard 14-plate oil-bath unit, but with plates mod­i­fied by Fer­odo to solve an early prob­lem of slip, since when it was bul­let­proof, though with a rather sud­den pick-up which once led to a gi­gan­tic wheelie on the Brands Hatch start­line! Like his tech­ni­cal idol and ELF designer An­dre de Cor­tanze, Mau­rice Ogier was an ad­vo­cate of low-down weight dis­tri­bu­tion, in or­der to lower the cen­tre of grav­ity and make for eas­ier han­dling. Fit­ting a fuel tank un­der the en­gine Elf-style was out of the ques­tion, but hav­ing chucked away most of the electrics there was a big hole be­neath the seat which Mau­rice filled with a care­fully-shaped 19.5-litre al­loy fuel tank – but how to get the fuel to the carbs, since grav­ity feed was now im­pos­si­ble? Hav­ing jet­ti­soned the bat­tery, an elec­tri­cal pump was out of the ques­tion; bear­ing in mind the bike was ini­tially built just for the bumpy Isle of Man TT Course, a fuel pump off a GS Citroën car was fit­ted, op­er­ated by a plunger from the mid­dle of the swingarm pivot sup­ply­ing a small header tank above the carbs. This worked well enough even on Don­ing­ton’s bil­liard ta­ble sur­face, but to be on the safe side Mau­rice also in­stalled a high-pres­sure me­chan­i­cal pump from a Lu­cas F1 car in­jec­tion sys­tem, driven off the drive side end of the crank. Just as well, be­cause the plunger pump packed up in prac­tice for the TT, in which Will Harding duly gained his cov­eted Fin­ish­ers Award, af­ter what might be termed a ‘lively’ ride! The rea­son for this was that hav­ing shifted the fuel be­neath the seat, Mau­rice had ob­vi­ously re­moved the stan­dard fuel tank, leav­ing the en­gine fully ex­posed. This not only meant that you needed earplugs to ride the bike thanks to the added in­duc­tion roar along­side the open mega­phone ex­hausts, but there was noth­ing to grip with your arms, el­bows or knees. By now I’d be­gun to take a closer in­ter­est in the bike’s devel­op­ment – it was some­thing dif­fer­ent from the Du­catis that al­ready pro­lif­er­ated in TT F2 and BOTT grids, and I could see it had lots of po­ten­tial, so Mau­rice and I agreed to team up for the fol­low­ing 1983 sea­son. We ran the bike on Dun­lop slicks for the first time at the in­ter­na­tional BOTT race at Don­ing­ton Park in Septem­ber ’82, fin­ish­ing an en­cour­ag­ing 10th over­all and fourth in the 600cc class in spite of the dif­fi­culty in chang­ing di­rec­tion caused by the lack of bod­ily pur­chase on the bike, but also the se­vere chat­ter from both ends as the stan­dard forks and swingarm proved in­ca­pable of with­stand­ing the stresses im­posed by the rac­ing tyres. Over the win­ter of 1983-84 the Ogier Laverda be­came a proper race­bike in­stead of a mod­i­fied road­ster, al­beit still em­ploy­ing the stan­dard frame. Many such Mon­tjuics were be­ing raced in Spain and en­coun­ter­ing the same han­dling prob­lems with slicks, lead­ing a lo­cal firm to man­u­fac­ture a heavy but very strong box-sec­tion swingarm which a Span­ish friend, Joaquin Folch, kindly sup­plied for us. Up front, a 38mm rac­ing Mar­zoc­chi fork with mag­ne­sium slid­ers and ad­justable damp­ing re­placed the crummy 35mm stock front sus­pen­sion, and we fit­ted gas Gir­lings at the rear, with a set of Dy­mag cast alu­minium wheels. A hand-beaten alu­minium shroud was fit­ted over the en­gine to give me some­thing to grip, as well as re­duce the noise, which even though it looked like a fuel tank (a fact which con­fused sev­eral race scru­ti­neers!) was ac­tu­ally open at the bot­tom. A vac­uum fuel pump, pulse-driven off the left hand ex­haust, re­placed the heav­ier Lu­cas unit. The oil cooler was shifted to the nose of the fair­ing, it­self a Mead­speed replica of the Bi­mota KB2’S body­work, to give a smoother air­flow down the side where it had pre­vi­ously been mounted. The cush-drive in the rear sprocket was re­moved

to re­duce un­sprung weight, chain size went down from 5⁄8in to ¼in, sav­ing three pounds in the process, and a lot of cut­ting and light­en­ing on the frame helped to achieve the very low weight, as tested by the scru­ti­neers’ scales at Assen in 1984, of 132kg dry, split 50/50% – against 179kg for the stock street­bike. The trio of stan­dard 254mm ca­st­iron Brembo brake discs with twin-pot calipers were re­tained, though the front pair were now fully float­ing, and in spite of their small size worked re­ally well. Along with this chas­sis work went a con­sid­er­able in­crease in en­gine out­put, mainly achieved in one day spent on Leon Moss’s dyno with a va­ri­ety of al­ter­na­tive ex­hausts. Even­tu­ally Mau­rice ended up with a pair of his own alu­minium me­ga­phones which yielded 71bhp at 9800rpm at the rear wheel run­ning on 36mm carbs, with a very flat torque curve of 28lbft/38nm from 3000 to 10,000rpm, which made the bike in­cred­i­bly easy and for­giv­ing to ride. Later, this out­put was pushed up to 74bhp when 38mm carbs still with a 36mm in­let tract were fit­ted for the 1984 Day­tona BOTT race. On 16/36 gear­ing the bike pulled 9800rpm on the Florida Speed­way’s bank­ings, and was trapped at 148mph. With higher gear­ing and more revs (Bret­toni’s TT2 racer was revved to 10,800rpm, one rea­son per­haps for its lack of re­li­a­bil­ity), the Ogier Laverda was a true 150mph bike – from only 579cc. In­ter­est­ingly, the dyno re­vealed that with the fac­tory two into one ex­haust, there was only 57bhp on tap!

“WE MIGHT NEVER HAVE STARTED THE LAVERDA PROJECT BUT FOR SHAR­ING A GRASSY BANK AT SIGN­POST COR­NER DUR­ING THE 1981 ISLE OF MAN TT WITH A MU­TUAL AMER­I­CAN FRIEND NAMED WILL HARDING.”

Chas­ing the For­mula 2 Cham­pi­onship, some­times with limited pad­dock fa­cil­i­ties.

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