BSA three-wheelers continued
After reading the BSA threewheeler YWA article in TCM, October 2021, friend and magazine regular Brian Young recalled the following memories.
“This photograph (right), taken in 1958 is of a friend’s 1937 four-cylinder BSA three-wheeler he bought as a BSA Scout. Later, we were told the Scout was a
BSA four-wheeled car. In those days it didn’t matter to us what it was called, we just got on and restored it. To be fair, it didn’t look much better after we had finished, except that you couldn’t see the road through the floor anymore… I seem to remember we used a lot of plywood!
“We were told its side-valve four-cylinder engine was based on the Austin Seven design – is that correct? It was a decent runner, turned out to be quite reliable apart from its brakes which were a bit iffy… I don’t think the back brake worked – a long cable if memory serves, which defied adjustment. Would I be right in remembering a combined gearbox/differential unit was mounted low down in front of the engines?
“The 1954 Sunbeam S8 in the photograph was mine. It was the only motorbike my mother ever liked. It didn’t leak oil on her path.”
Thank you, Brian, for the memories of your friend’s Beeza three-wheeler car. And following on from recall of restoration 50-plus years ago, the following may amuse.
In 1962, I helped my father Oskar rebuild a circa 1939 Fiat Topolino 500. The machine shop which machined the crankshaft got it so tight after dealing with the plain bearings to big ends, the engine they returned to us wouldn’t turn on the starter or handle. Dad complained, to be told it would be okay and don’t strip it, because you’ll invalidate the three-month warranty. So the car was towed in gear for a few hours until it would turn on the handle, then after an oil change, it was started and run for hours with the garden hose into the radiator to ensure a constant flow of cold water. Then the car started to be driven and apparently it completed over 20,000 miles before chassis rot ended its days and the owner scrapped it. During this time the engine never gave any problems.
Your choice of plywood during your 1958 restoration of the BSA three-wheeler followed perfectly factory practice – in fact, BSA farmed out coachwork for these trikes when the factory was stretched. The factory built them with a channel section chassis with central tube which tapered to the single rear wheel. The bodywork’s ash skeleton skinned in plywood was secured to the chassis and plywood was used for the floor.
Sources state the 10hp 1074cc side-valve four-cylinder engine was based on Coventry Climax design, with a few sources stating the latter built some engines for BSA. Having worked on a single BSA four-cylinder three-wheeler/car engine and a couple of Austin 7 units, I can see similarities in design, but this isn’t surprising as the Austin 7 engine was one of the best small car engines of the period which sired many designs, so it would have made sense for Coventry Climax to have had a look at an example or two.
As you rightly remember, Brian, the transmission was mounted ahead of the engine. Also, what is quite apparent is that although fitting the four-cylinder engine to the existing V-twin three-wheeler wasn’t too difficult, getting the naturally heavier trike under the required 8cwt for tax concessions was. Apparently, BSA struggled with the TWxx 10’s dieting regime.
The four-cylinder BSA threewheeler was manufactured for four seasons, 1933-1936, but there is evidence new models were still being sold and registered in 1937 and seemingly into 1938. They were never given a name, but were coded TW33 10 to TW36 – 10 where TW was for Three Wheeler, 33 to 36 the season year of manufacture and 10 meant 10hp.