6 Classic British 500 Twins from the 1950s

This time it’s the six of the best British 500cc Parallel Twins of the 1950s

this time it’s classic British 500cc parallel [Music] twins for some there’s really nothing more British than a parallel twin 500cc motorbike now while companies like horx and Germany will claim to have influenced the design of this speed twin this is of course nonsense the Triumph is a very different design and incidentally what people often forget is it’s not the first Triumph parallel to an E the 6th One Beat it home by a few years and in fact the parallel twin layout itself is much older than that Steven’s Brothers even before they formed ajs manufactured engines for other manufacturers and included in their catalog before the first world war parallel twin engines but of course it was Edward Turner speed twin that really popularized the layout and so so here we have some classic British parallel twin 500s from the 1950s Triumph Speed twin Triumph’s chief designer Edward Turner introduced the Triumph Speed twin in 1937 with sales beginning in early 1938 the mic had a 490 CC 360 Dee parallel twin overhead valve four-stroke engine it made 27 horsepower at 6,300 RPM and had a four-speed foot change gearbox then pretty much the standard by the late 30s and the genius of the speed twin was of course that it looked a bit like a 500 single singles were the bikes to go to if you wanted a sporty job in the 1930s but while it looked like a single it didn’t perform like one it had better performance it was smoother and developed more torque and it was also lighter and more compact the many of its single cylinder opposition bike is best remembered in its ARA red paint job and the pre-war machines this was was set against a beautiful Chrome tank which included an instrument panel built into it the post machines were vaguely similar although of course they now had telescopic Forks replacing the girders and this 1946 bikes also included edwardton and sprung Hub as an option this provided a small amount of movement to the back wheel in the hub itself as the name suggests wasn’t terribly effective but it did give at least some cautioning in 1949 would see the introduction to e aell front end essentially a cing around the headlamp which just tided the whole front end up very nicely into the 50s we would see those classic jukebox style tank badges in 1953 D would introduce battery coil ignition to their bikes for the first time and into the mid-50s we see proper swinging arm suspension for the first time Drive never did bother with plunges on their parallel twins the speed TRN and its sportier brother the T100 would go on until 1959 at this point we would see the uni construction 5T models replacing them these were of course closely based off the earlier 3A or Tri 213 50s and those are course have quite different machines which we’ll talk about in another video perhaps the BSA A7 BSA is A7 is one of those machines that doesn’t have a single designer early work on the bike had started before World War II and had been led by Valentine page he had previously designed the 61 for triing from the early 30s and indeed the A7 certainly it earlier versions does bear some resemblance to that bike’s basic layer but if paig return to Aerial during the war bike would be fairly developed by Herbert Parker and David Monroe before its release in 1946 although later development work was continued by bir hotwood bike us an air cooled 495 CCC parallel to an engine producing 26 horsepower with a top speed of around 85 mph and the engine’s basic layout included a single cam shaft mounted to the rear of the cylinders rather than the TN 4 and after cam shafts employed by the Triumph La machines deployed a long stroke of some 82 mm but the post 51 bikes are actually based on the 650 A10 so have a revised dimension of 66x 72.6 in 1954 would’ see further revisions this was the year they introduced The Swinging arm frame and the engine was revised to be a more conventional separate engine and gearbox system because the plunger frame bikes had had their engines and gearbox actually bolted together but this design had limited the choice of gearboxes available this meant that Post 54 bikes were able to use pretty much any gearbox from bsa’s range including of course the race gear boxes and so the A7 would continue on until the end of the 50s and into the early 60s with the only addition being an aluminium head for the more sporty models however the 1962 introduction of the A50 unit construction bike would finally see an end to the sturdy old A7 the ajs model 20 the AGS model 20 and its sister bike the maxus G9 were first shown at the ill Court show in 1948 although sales didn’t start in big numbers until the summer of 1949 the Cy parts were all pretty much standard AMC fair with a pivoted fork frame and of course a telescopic front forks but the styling was bang up to date with its nice Chrome finished tank dual seat and of course megaphone silencers the engine was however a little unusual it used four and half cam shaft the same as Tri but it had a unique Central bearing not used on any other British twin this was a nice piece of engineering but it didn’t actually make the machine any smoother than any of its competition and the bike’s performance was pretty much the same as the rest of the twins on the market but unfortunately the machine was never a great salout compared to its opposition and despite some very nice engineering the bikes are often viewed as old men’s bikes bikes and this whole situation was not held by AMC’s very poor relationship with the Press of the day they simply wouldn’t let their bikes out for testing so unfortunately when the bike was dropped the range of 58 few people even noticed the aial kh500 the aerial kh500 Field Master was introduced in 1948 and like so many variable designs it was the work of Valentine paage the 500 engine was not as as often suggested based on an A7 but was a quite different design although of course there will be some similarities simply because the two machines do share the same designer after all the khc’s 498cc engine produced 28 horsepower at 6,500 RPM there was of course a four-speed gearbox telescopic front forks and a rigid rear end initially although plunge suspension would eventually become available in 1951 when the machine would be joined by the AG 10 based 650 by the mid-50s both bikes had gained a proper swinging arm frame but this didn’t last for long because in 1957 the entire fourstroke range was deleted to make way for the excellent two-stroke leader range but of course the Cyclone alas 650 based on the A10 would remain in production until 1960 the Norton Dominator 88 bit hotwood had developed the Norton engine between 1947 and 1948 though the Dominator was not actually on sale until 1949 first bike the model 7 Dominator had a 497 CC parallel to an engine with the usual 360 crank unusually the single cam shaft was mounted right at the front of the engine which was otherwise pretty much conventional for the bikes at the time although of course the bike did have a cast in Rocker Box something which Triumph engines would never have the engine was a long-stroke design with a 66x 72 B and fairly mild stens of tune in its initial form ears were fitted with plunge suspension this was changed out for swinging up suspension in 1953 the year that would also see the introduction of the model 88 also known as the dominated Deluxe this put the 497 cc engine into their n and featherbed frame but despite it sporting protentions the 88 was a fairly modest performer and quality control issues of the factory would limit production to around 200 machines a week the engine however was R for tuning and was enlarged to 600 later 650 and eventually 750 and even 850cc versions of the engine were developed for the Norton commando but of course all that is way off in the future voland field 500 twin and meteor minor when it comes to names War Enfield are really Past Masters at coming up with a just the right name for a particular bike Continental Interceptor meteor and of course let’s not forget the bullet so with that in mind it’s a little surprising that when Royal Enfield did introduced their first parallel twin in 1949 they simply called The Machine the 500 twin honestly but it took them literally minutes to come up with that one the engine have been the work of Ted Paro and Tony Wilson Smith in the first been show in 1948 and to some extent the engine does bear resemblance to the big singles at the bullet there is for example a cast in oil supply chamber and the skirts of the barrels were pressed very deeply into the crank case giving the engine a squat and I think quite purposeful and modern appearance the engine was in fact based on the 248cc model S engine but doubled up this had a boring stroke of 64x 77 and produced 25 horsepower at 5,500 RPM and the the bike could run in this form until 1958 with of course some styling upgrades at that point the bike is replaced by the meteor Miner this represented a major upgrade of the earlier bike it had improved beef up bottom end and a shorter stroke so it was much more powerful and the miner would run on into the 1960s what collections of bikes would you like to see us do a video on maybe you got a bike we can use for a test ride either way get in touch below hope you enjoyed that video if you did don’t forget to like And subscribe and of course thank you very much for watching