1954 Ariel 499cc HS5 Mk1
Registration no. 667 YUL
Frame no. KSS 277
Engine no. PS 259

* Delivered new to the USA
* Matching frame/engine numbers
* professionally rebuilt engine

By the mid-1950s the swinging-arm frame's superiority had begun to be recognised in the scrambles and trials worlds, overturning the conventional view that a rigid frame gave better grip. Ariel was one of the last manufacturers to introduce a frame with rear suspension, the prototype of what would become the HS5 first appearing in works development chief Clive Bennett's hands in 1952. By the time the production HS5 arrived for 1954, many competitors, including some Ariel works riders, had switched to rival makes. The new HS5 enjoyed some high-profile successes but by then it was too late. There was an abortive Earles-fork Mk2 version that never made it into production and also the Mk3 (the original being re-designated Mk1) a 'street scrambler' that was built in a softer state of tune, making it road useable. The newcomer was aimed squarely at the US leisure market but unlike the Trophy and Gold Star on/off-roaders produced by partners Triumph and BSA respectively, was not listed for the UK, though it is believed that a tiny handful were sold new in this country. A magdyno, lighting set and lower exhaust system with silencer were the major additions to the basic scrambler specification. Sadly, after little more than two years in production, the HS5 MkIII went the same way as Ariel's other four-strokes, being dropped in 1959.

This Mk1 example of one of Ariel's rarest post-war models was despatched in August 1954 to Johnson Motors Inc of Pasadena, California, USA (see dating certificate on file). It is not known when it returned to the UK but at some time during the late 1980s/early 1990s seems plausible as there is a purchase receipt dated July 1991 in the history file together with a quantity of bills for parts from marque specialists Draganfly Motorcycles dating from this period. The owner at that time was one M Ramsay of Foulden, Berwick-upon-Tweed.

The current vendor bought the Ariel around five years ago, since when the engine has been rebuilt with the assistance of his father, a respected professional engineer. Works included re-linering and re-boring the cylinder barrel and fitting a new piston/rings, a new exhaust valve and new valve springs, the latter being specially made. Other noteworthy features include a new, correct Amal Monobloc carburettor; re-conditioned oil pump; new wheel bearings where necessary; and new stainless steel rims and spokes. Presented in generally very good condition, the machine is offered with an expired MoT (November 2013) V5C registration document and a most substantial history file of bills, price lists, technical literature, etc (inspection recommended).