Velocette in the 1971 Castrol 6 Hour Production Race….

1970 saw the first of what became an almost 15 year span of 6 hour production machine races, held, except for one race, at the Amaroo Park Raceway, a 1.2 mile tight clockwise circuit on the Northern outskirts of Sydney.
That first year saw a relatively unknown rider, Craig Brown, on his “ride to work” ( later to prove his undoing), CB750/4 Honda.
Craig led the race until near the end, when he ran out of front brakes…he hadn’t the money to start the race with new brake pads and paid the price with a retirement, leaving the late Bryan Hindle and Len Atlee to win on the Ryan’s of Parramatta Triumph 750.
Well at this stage I was still an “occasional racer”, still had my Velocette Venom Thruxton ( engine number VMT458), which I purchased new in Feb.1967 and so took the plunge and entered the 1971 event, with former ex-International Dennis Fry and John Herrick as co-riders, both also Velocette enthusiasts. My good friend Jim Day was the designated team mechanic.
Now it was a long time ago, so I can let some “skeletons out of the cupboard”…not figuring on getting on the leader board in the 500 class, I decided to “help” the VMT.
I fitted coil valve springs back in, rather than the original hairpin type. We never revved it past the designated 6,200rpm maximum, but the hairpins usually settled and valve float would set in lower and lower as the race progressed, so the coils ensured this didn’t happen and should you miss a gear, the resulting over revving wouldn’t see a valve kiss the piston. This happened in unofficial practice some weeks before with hairpins fitted and a bent Nimonic 80 exhaust valve resulted. An urgent telephone call to L.J.Stevens Ltd, the Velo people in London, UK, saw a replacement airmailed out in time. As well Thruxton’s are marginal in engine pinging, so working at a scientific research establishment, CSIRO, I found out the dye used to dye the local Super petrol ( 96 octane) we had to use.
I obtained some and using Esso 115/145 aviation fuel, normally purple in colour, I dyed some 20 gallons of fuel to the straw colour of Super..
That was one problem out of the way.
The kickstarter fouled the exhaust pipe, so I re-bent it and replated it to standard…removed the dynamo belt and fitted a broken one left lying in the bottom of the generator cover. The battery was a hollow box and no battery needed, there being no current generated.
I might say at this stage, that the supplementary regulations for this race were so strict in requiring a standard specification. There is no doubt that not many of the “production” racers in the IOM Production TTs would have complied…
Dennis Fry had an ankle injury from several IOM TT crashes in his continental circus career in the early 1960s, so needed a rocking gear pedal. I petitioned the organising committee for permission to fit one.
I also had a bent in that era to use aviation oil and so we eschewed the free gallon of Castrol GTX for Mobil Aero Oil 80. Tyres were to be road tyres and I favoured Metzelers’ so fitted C5 front and rear.
Official practice went off all Ok and we agreed that I would ride the first 2 hours we would then refuel, Dennis Fry would ride next and depending on our position in the race, either John Herrick or Dennis Fry would do the last 2 hours. This leads to an interesting incident at scrutineering... Dennis Fry fronted up with his Cromwell "Pudding basin" helmet ( you can see it in the pictures...likely this was the last time such a helmet was used in competition..)...the examiner baulked at Dennis's helmet... seizing the opportunity, Dennis replied, "Listen mate, this helmet has survived 5 crashes in the IOM TT at over 120mph" and pointed to the IOM TT compliance stickers on the helmet etc. Flumoxed, the official passed it, when in hind sight it should have gone into the rubbish tin....
With the tank capacity and fuel consumption, we had only 2 stops for fuel compared to 4 stops for most of the others. The exception being the large BMWs who also could do 2 hour stints.
The start was a nightmare..a Le Mans start requiring you to sprint across the track, mount and of course we had to kickstart, some others also kicked, other used electric starters. The noise was incredible as the 64 bikes burst into life…I couldn’t tell if the engine was going ( yes…I have a tacho and a quick look should suffice, but the adrenaline pumping, I forgot), so it was a slow start. However I quickly settled down and my lap times were consistent and we were placed about mid field in the 500 class. The pit stop was uneventful and Dennis Fry set off and soon his European racing experience showed and he was lapping consistently a second faster than me…then he disappeared!
Anxiously we waited for him to appear or news…then it came -he’d crashed heavily in the Brabham loop, the bike end over ended, destroying the rear rim and silencer and bending the frame. Dennis was carted off to hospital…128 laps and we were out….
Dennis recovered and we straightened the frame and I made plans to ride again next year. It wasn’t to be, for what reason I can no longer remember.
I perused the lap sheets and figured we would likely have done 285+ laps, this would have got us into 12th place in the 500 class, let’s put this into perspective…out of 13 finishers in that class .
Still you know what they say…the old “if”…”If your Aunt had balls, she’d be your Uncle…”
There were 15 starters and 10 finishers in the Unlimited class; 26 starters and 13 finishers in the 500 class; and 23 starters and 8 finishers in the 250 class.
The Thruxton was the only Velocette to have entered in the races history and if you want to be catty it was the only Velo not to finish…..

Where is my old Thruxton today?.... it passed out of my hands in 1980 to Tony Keene, who finished its repair/restoration and was eventually sold on to Western Australia where it is today.

Left click on photos to enlarge.
Most of the photographs are credited to John Hiscox of Hisco Photography, Sydney.