Jim Day's MOV Velocette "Thruxton".....

The title of this current post is a little perplexing....
A Velocette Thruxton MOV....
Of course its a special...but let me explain.
During 1966 I saw the first of two Velocette Thruxton models that were imported into Australia via the Victorian Velocette agent, Frank Mussett Motorcycles....
Yes I wanted one, so I sold my 1961 Venom and stumped up the deposit...AUD$360 from memory on the AUD$990 full price to the Sydney motorcycle agent, Burling and Simmonds of Auburn...the bike was due in January 1967 but subsequent delays saw me not get it until late February.
I lived with my father and sister in Maroubra, a suburb of Sydney and my next door neighbour was Jim Day, a Velocette rider and enthusiast and a lifelong friend.
Some time during the year Jim decided, with the increasing cost of the green slip insurance on motorcycles, which had risen sharply, that he needed a 250cc machine to get into the lower registration bracket. 
His father, Tom mentioned he had a 250cc MOV Velocette he'd sold a chap for 12 quid a few years back and that he'd never paid the full amount and really it was still his....
The hunt was on...
By some sleuthing we tracked the bike down and as it turned out it was finally found leaning against the wall of a lane awaiting rubbish removal in a suburb nearby.
Jim waited with the bike, I hot-footed it off to get a trailer and we had our 250.....
Stroke of luck eh.....
But we also had a spare RS Velocette swinging arm frame, so the idea was hatched by Jim to fit the 250 into it, model it on my new Thruxton with some engine work based on the 250 Royal Enfield crusader, an 8" BSA front brake- the cast iron drum lightened with holes bored in the back of the drum with large aluminium plugs and an effort made to convert it to 2LS operation...more of this later....
So all the "excess" lugs were removed from the frame for lightness ( sidecar etc), the oil tank moved back a la VMT and I'll let the photographs tell the story......
Left click on the images to enlarge.....

I can see by the date on the registration label these photographs were taken in 1968.

The engine as mentioned was modeled on the 250 RE...carb. spacer, GP Amal carbs were "a bit thin on the ground" in Australia around then, especially smaller bore ones and I'm unsure why we didn't use an Amal TT carb, so Jim settled on a 1 and 1/16" Amal 376 monobloc . Cams were of the M17/8 Venom timings, which later proved to be unsatisfactory as the bike sure revved but "wouldn't pull the skin off a rice pudding", well it was back to the M17/7 MSS style.
A piston was made by local Veloman and piston maker for most of the Australian racing fraternity, Sid Willis.
At the time it was of course in Y-alloy and as such you need fairly wide piston clearances to avoid seizures.
The cylinder head was from an alloy MAC Velo in an effort to get some oil tightness. 
Alloy pushrod tunnel, the 12- gearbox fitted, alloy wheel rims.
And in the end it went alright but the concensus was the frame setup was just too heavy for the 250....

I mentioned earlier the 8" BSA front brake, converted to 2LS operation which showed great potential on paper.
We suitably lightened it, but when used it was pretty hopeless as a "stopper".
We tried different linings, chamfers on the linings etc and in the end in desperation the actuating arm the cable pulled on was lengthened about and extra 1".
The brake then worked a treat....

The photo shows the brake prior to the lengthening of the brake arm....
Where is it now.....
Well a friend from NZ, Ernie Williams came over to ride in the historic race at the big Easter Motorcycle TT races at Bathurst around the early 1980's.
I removed the "un-necessaries" from the MOV and we had a racer for Ernie.....
Bad news was it dropped a valve with the ensuing damage to the piston and cylinder head combustion chamber surface.....
Off to Sid Willis for a piston and after waiting the requisite time...Sid was never rushed...probably 9 months....I returned to find Sid had repaired the combustion chamber and valve seats so the bike was ready to go back together.

The head and piston after I collected it....
Since I've set this post up I came across some more photos of the blown up head....

Come forward to earlier this year.....
Yes the MOV laid "waste", un-assembled all those years.....
Jim Day visited NZ in February and borrowed Ernie Williams 1956 MAC again to ride in a rally in the South Island of NZ....
You bet.... he dropped a valve in Ernie's engine...
JD is returning from NZ tonight after spending a week there repairing the engine and he took over the piston and cylinder head from the Thruxton MOV, so sadly I fear it will be no more.....
The frame setup wasn't completely "idle" all this time....we fitted a Mk.2 KSS engine in it for several years also a long time back, but no photographs appear to have survived, but as I write this, the setup now has a 500 Velo engine in it....
Jim calls it "his big MOV".....