The Auriel explained
In OBA 50 Out & About we featured a shot of a mystery motorcycle spotted by a reader in Foxton, NZ. The owner, Shorty Cole, also from Foxton, has come forth with an explanation:
I received several excited calls the other day about a photo of my bike (OBA 50 Out ‘n About P84). The frame is a 1956 Ariel Huntmaster, the forks are Norton Road Holders, and the wheels are BSA full width alloy. Gearbox is off an AMC single, and the motor…an Austin Seven. Yep, after a few beers last year with some fellow riders, I mentioned that I thought this might work, so away we went. It did take a lot of figuring out, and reworking a bit, and around Christmas I started her up and went for a blat down the road. I am not running a flywheel, and with new twin Amals and the four-into-one exhaust, she really does go quite well. I did receive a bit of stick like” use a Briggs and Stratton” that’s 25 hp...when you ride the bike, at around 7-8 hp it’s the torque that does the job. At 2,300 rpm she is doing about 85 km/h, and will rev to 6,500, with 4,000 to 5,000 usable. The drive to the gearbox- the old flywheel was turned down as this is not required in its original form. I am using it only to retain the oil, and to give the sprocket something to tighten up against. The sprocket was bored out and a thread cut on my lathe, and two flats milled to allow a large spanner to tighten it. A large lump of aluminium was turned/milled to fit neatly into where the starter motor was previously fitted, and using three selfaligning bearings, a stainless steel shaft was mounted, being braced at each end. These are all slotted to allow adjustment on the driving chain. A taper-lock sprocket takes the drive to the clutch, which then completes the whole drive cycle. The engine was completely rebuilt, balanced, and some small mods carried out. Two new carbs were fitted and feed the fuel through two long tubes to the intake of the engine. There were a few problems constructing the four into one exhaust, but in the end it seems to work ok and sounds great. To cool the engine I used a radiator off a Yamaha LC350 coupled to a Toyota Prius 12volt electric water pump, wired through a rheostat to adjust the flow to adjust the water temperature. So far this seems to be working well.
Starting the beast is just like any other old bike, key on, ensure water is flowing, tickle the carbs, full choke and she normally fires up after a couple of prods (unless there’s a crowd watching). Once warm, open choke and go. It is a very smooth bike to ride, and extremely responsive, both when opening and closing the throttle due I guess to no fly wheel. As you can imagine I was the brunt of much good natured banter – like use a Briggs and Stratton, twice the horse power – it is a really impressive little bike, idles around 1500 rpm and will rev to 6,000 . Now just a few things to finish, like a generator and the front guard… then the next project is...