Fronthub/brake

I

nthe world of performance engines,

John AlfredPrestwichsort ofcornered

themarket earlyon, rightat thedawnof

thesenew-fangled internalcombustion

engine things peoplewerefitting into

bicycleframes.

JAPdid produceamotorcycle

themselves for three or fouryears but

rapidlyrealised their forte layinsupplying

engines to others. Being based in London

rather than the Midlands kept them

remarkably independent of the two

wheel industryand their diversity into

producing engines for cars, aeroplanes

and the utility market meant theywere

not dependent on anyone industry.

Aseemingly unconnectedevent at High

Beech, London in 1927 when theUKwas

shownthis newdirttrack sport –soon to

be speedway–fromAustralia ledtoJAP

becomingthe engine of choice forthis

frenetic sport.Settlingon500ccengines

the speedwayracers neededareliable,

powerfuland light engine torocket them

arounda400 yard oval for four lapsarace

and theJAPSpeedwayengine did dutywell

into the1960s.

Since comingback into motorcycling

aftera45-year lay-off CecilPearson, a

formergrass and scrambles racer,has been

awelcomesight on tracks foranumberof

years by bringing hisTeam JAPoverfrom

NorthernIreland and whilemostofthe

bikeshebuildsfor hi steam arehousedin

Rickman frames, thisone isadeparture

from that.The basis of CecilPearson’s

JAPMXerisjust such an engine andhe

has slotted it intoaspeciall ymade Victor

BSA replica frame builtbyHarryStitt, one

of histeam racers and talentedengineer.

Usinga1930s speedwayengin emated to

an AMCgearboxwithaNorton clutchto

provide drive givesalightand powerful

machine.The frameis from T45 tube and

lighter than theotherbikes in theteam –

Cecilclaims it hasto be as he’sanold man

now–Marzochhiforksatthe frontand

Rockshocksatthe backsoak up the bumps

on thetrackand theplotrollsonaGrimeca

rear huband an unknownfronthub.

SeriouslyCecil would like to know what

the front hub is as noone canrecognise it.

Also Italianisthe carburettor,aDel

Orto andit’sbig enough to feedlarge

amountsof methanol into the engine

whichall helpsto keep the JAPatthe

frontof thepack. Ignition isaspecially

designedsystem whichafriendofCecil’s

devised andsuffice to saythereare no

ignition problems...

So,awell sorted andtruly classic

machine capa bleofmixing it withthemore

modernstuf fonthe trac kwhich is whywe

sayyou need aJAP inyour shed.

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AUTUMN 2019 | 17