Classic Racer — September — October 2017

CLASSICRACERINDETAIL

48 ClassicRacer

HOWITENDED(NOTAHAPPYTALE)

The BelgianGP at Spa becamethe bike’s unheralded

finalswansong, withKeith Campbell again the lone

V8 Guzzirider in the 500GPrace held on July 7, in

whichhesurged into the lead ahead of Surtees

and Liberationtheir fours. But after smashing

Gilera’sexisting lap recordwith alap averaging

190.13kph/118.14mph, during whichthe MotoGuzzi

V8 wastimed at atruly remarkable286kph/178mph

alongthe MastaStraight,and seemingly on the

waytocertain victory,the Aussie cameto ahalt in

asecure leadwithabroken battery lead!Although

nobody knewit at the time,thisturnedout to be the

MotoGuzziV8’slast race.In pre-racetestingfour

daysbefore the Italian GP at Monzaon September 1,

the new Australian350ccworldchampion crashed

the 50

Curva

his pe

of the

On

Geoff

ride t

joinin

for th

test n

week

road

by the

withf

Gilera

0 0V8atthe fast

aAscari and broke

elvis, putting him out

erace.

neweek later champion

fDuke, wasdue to test

heV8,with aview to

ngthe MotoGuzzi team

e1958 season.But the

never happened. Instead,two

slater,onSeptember 15,the

racingworldwasdumbfounded

eannouncementthat,inconjunction

fellow 1957 worldchampions Mondial and

a,MotoGuzziwas withdrawingfromracing.

The23mminlet/21mmexhaust valves

were set at averymodern58º total included

angle, runninginbronze guides but with no

insertsfor thevalveseatsowingto machining

difficultiesbackthen, whichmeant thatas

these inevitably wore,the cylinderhead

became scrap.

Eachvalveused dual Alba coilspringsand

wasoperated directly by thecams via bucket

tappets, eventuallywith 6.5mmof liftfor the

1957 season (previously6mm),anapparently

minorchangeeethat Carcanosaidgave

considerable extra powerwhen combined

withnew,mooore aggressivecam profiles.

Thefour ovvverheadcamshaffttts–two each

perbank of cyyylinders –were driven by atrain

of six straighttt-cutgears enclosedin atiming

case on theright side of the engine,with a

single largepppinion driving the inlet camshaffttts

foreachbankkk,and the corresponding exhaust

camsinturndddriven offthose.That large

central pinionnnalso operated the water pump,

as well as theeesingle two-stage oil pump

mountedbennneath it that supplied the 3.5l of

lubricantto thhhethree central mainbearings

and the fourcccamshaffttts, as well as scavenging

it backtothe spineframe’s central tube,

which doubleeedasanoil tank.Thedifficulty

of lubricating crankpins in an assemblywith

full-circlecrannnkwebs wasresolved by

collecting the

overflow fromthe

centralmainbearings

in annulargrooves

in the adjacentweb

faces, andfeeding

it tothe crankpins

by centrifugalfling.

Thecylinders were

numberedright

toleft, frontthen

backand, after some

experimentation, the firing

orderwas 1-8-3-6-4-5-2-7,with

CEV coilignitionrunningahefty

044 MotoGuzzi500 V8_SEP.indd 48 26/07/201715:23:24