My Heavyweight 500cc Ariel Trials Iron
Q  By Dave Blanchard
I learnt to ride motorcycles when I was about 13 years old, this was made possible because my Dad would let me have a go on his 1933 600cc Panther Redwing combination when a deserted minor road was safely available. But, as a young schoolboy my enthusiasm for motorcycles started many years before that first uneasy, but wonderful experience. However, this story is about my Pre-65 trials bike that works hard for its keep.... just as any British Bike should. I do not believe in over polishing any of my old bikes, but prefer to substitute those cleaning hours for mechanical maintenance... plus riding. My Girder forked Ariel is not entirely original (unlike Trigger's Broom)....but is more than eighty per cent 1938 500cc single with some Red Hunter parts mixed in. The older and more respectful name for it would be a "Special"... but these days "Bitsa" is the commonly used term. However, "Special" assumes a degree of build skill is incorporated, and it is. Originally made on the production line at Ariel's in Selly Oak...Birmingham. In its later years was converted into a Vintage road racer... some of the setup being assisted by Owen Greenwood of 3 wheeler mini fame. Apparently an engine blow up finished its Vintage road racing days and it was then bought by Ray Blackwell who converted it into what he called his "Arbuthnot Trials Special". Ray had done some useful mods which included a shortened army frame with the engine bottom rails removed, plus standard Army front forks because they are longer and therefore gave more ground 14
clearance... as does the Army frame. A small and beautifully made central oil tank was fitted just above the gearbox, this holds about 2 pints which is quite adequate. The engine has never overheated... even on LDT trials. Ray also fitted a low compression HT piston and this proved a great help in softening the power delivery. He retained the standard Ariel rear wheel sprocket at 47 teeth but by changing to a 17 tooth engine sprocket and 16 tooth gearbox sprocket, would get the gearing low enough for old bike trials as they were set out in 1982. When Ray's arthritic wrists became too painful to pilot it on the rough it was sold to his good friend Dennis (Jim) Townsend....who being an ex Army man always kept the Ariel absolutely immaculate...unlike me. Jim had great fun riding this bike having several successes in Pre-65 trials events around the South and South Eastern centres. When Jim also gave up competitive off road events I narrowly missed the chance to buy this Old Warhorse. But! Less than one year later it was up for sale again from Alan Ward the latest owner, who lived in Brighton. I did not miss it the second time around! My first competition on this Ariel was at the VMCC "Festival of 1000 bikes" back in 1994. During the event it was oiling spark plugs but I cured that a few weeks later with new valve guides and piston rings. Screw on canister oil filters are a really good idea so a 2CV one was fitted at the same time. Soon after this the monobloc carb was changed for a concentric, because with this type of carburettor the mixture strength is not affected by angles of lean. Unfortunately early Concentric's, seemed to be made of cream cheese, so scored slides and worn bodies were a natural way of life
