Monday, 25 April 2011

Charlie Bruce and the 250cc DOHC Velocette

This post is a brief introduction to the final Velocette racing motorcycle built by Charlie Bruce.
Charlie Bruce from Motherwell was a stalwart of the Scottish 250cc racing class. It was Charlie Bruce who go round the paddocks ensuring there was a good entry for the 250cc class throughout the 1950’s. Without Charlie’s passion for motorcycle racing, the 250cc racing class in Scotland would have probably ended.

Charlie Bruce at Beveridge Park
Charlie worked for the council in Motherwell, but had had tough times in WW2. He was at the ‘Death Railway’ (Burma Railway) and was a Prisoner of War. Charlie had some terrible treatment and it was only his dream of racing motorcycles that helped him survive his ordeal. During his time as a POW Charlie even produced the drawing of his racing machine using charcoal.

Charlie Bruce
Charlie Bruce was a very good rider winning the Scottish 250cc Championship in 1950 on his homebuilt bikes. Charlie was a Velocette enthusiast and until 1958 he rode an ex-WD pushrod Velo. There were various incarnations of this machine – I might go into these in another post at a later date.
Charlie was good friends of Joe Potts and much of the preparation work on his machines was done in Joe’s Bellshill workshop. Charlie became heavily involved with Joe’s own racing team, helping riders such as Bob McIntyre, Alastair King and Jimmy Buchan. Charlie was very well liked in paddocks across the UK and was well known by all the trade barons. It was because of this that Charlie became a bit like team manager for the Potts setup.
For 1958 the Potts team had been doing much work (see posts on the Desmo etc) developing new bikes. Joe made sure Charlie was not forgotten and talked with Bob McIntyre about getting Charlie a bike to replace his old pushrod Velocette. Bob organised the purchase of an ex-Works 250cc NSU Rennmax twin engine from Reg Armstrong for Charlie. Charlie kindly refused the NSU engine, saying he would rather finish second on a British bike than win on a German one! (he was an ex POW from WW2). It was back to the drawing board to find something for Charlie. Bob then located a 250cc DOHC Velocette engine that had been built by Doug Beasley. Bob paid Doug £257 for this engine.

This DOHC Velo engine was to be the basis of Charlie’s new machine. The engine had a bore and stroke of 68mm x 68.25 mm respectively. The crankcases, cylinder barrel and timing gears were all Mk8 Velocette KTT items. A special flywheel assembly was machined in order to reduce the engine stroke and the barrel was sleeved from the standard 74mm bore. An old Velocette factory racing cylinder head casting was machined and fitted with KTT valves which were reduced in size. The cambox was of Beasley’s own design and was clamped to the cylinder head by 16 ¼ inch BSF studs and nuts to faces machined on cylinder head. Standard Mk8 bevel gears took the drive from the crank to the cambox, but the flanged bronze bush which normally support the vertical bevel shaft were replaced by taper roller bearings. A 1¼ inch Amal GP carburettor was used with the engine. The engine produced 26.5 BHP at 8,500 RPM.  A should add here that this was the specification of the engine as first used in 1958. Over the coming years the engine had the Bellshill treatment and was modified heavily for extra performance.   
To house the engine a Razorblade frame (like the ones Bob was using for the 1958 season) was built by Alec Crummie. A Velocette 4 speed KTT gearbox and clutch was used. Shortened Manx Norton forks were fitted. A Manx 2LS front brake and Ariel/BSA type rear brake were laced into 19” rims. A Lyta aluminium petrol tank housed both the petrol and the engine oil in a section at the back of it.
I will add a follow post sometime giving some ideas what happened to the bike.

1 comment:

  1. I bought this Velo from Dennis Gallagher back in 1963 and entered it the 1964 Manx Gran Prix. Had a ongoing mechanical problem and did not complete enough laps to qualify. Also entered the '65 Manx but switched to a Greeves Silverstone and place for a silver repelica.
    It was a great handling motor cycle there was not a bike it could not out corner, but just lacked power. That was when the two strokes where coming on strong and the Areomachi was a strong contender. The one change I made on the bike was an Oldani rear wheel and brake, the Ariel hub weighed a ton. The frame also cracked above the swing arm on the main down tube. The gent who repaired it told me some of the history of the frame, Bob Mcintyre had them built to house a 350 Manx engine, but the backend whipped to much with the power from that engine. He then mentioned what caused the crack in the frame and problems they had could have been resolved had they extended the plate that held the swing arm down to the bottom tube of the frame instead of the triangle plate that only attached to the vertical down tube. Sold the bike in 1965 to somebody in the Midlands. Jim Dinnie. dinniejm@yahoo.com

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