I don't know about that particular oil but I believe that most 'car' oils contain friction-reducing additives which are bad news for a clutch. This is one reason given for using only the approved oils in modern motorcycle engines as the engine oil almost always lubricates the primary drive and gearb...

There is a copy of the Motor Cycle for October 25th 1928 road test of the Colt
available in the Members Only Document Repository in the cub's website.

It's technically a Black Ariel so you want the Black Ariel Spares Scheme.

If you can provide some dimensions I'll look in my box of NOS but unidentified valves.

Did Ariel provide replacement frames already numbered or were they left blank?

Years ago I had a new postwar rigid frame which I passed on to Draganfly when they were still in
London and as far as I remember this frame was not numbered but I'm not sure now.

The BSA yokes not only have the stanchions closer together than the Ariel half-sided yokes they also somewhat 'shorter' and won't fit into an Ariel frame. My understanding is that later, full-width Ariel forks have the same stanchion spacing as the BSA. This is speculation on my part as none of my A...

Somewhere I have a photo of Ron Langston on what is captioned as an HT3 with the Ariel half-sided front hub and my HT5 from 1957 also has an Ariel half-sided front hub. It was a production bike being sold in Leeds but it does have BSA yolks and the hub has been narrowed to make it fit, something I d...

One point in the BSA Otter webpage which puzzled me was the statement that the HT3 had a BSA 7" half-sided hub rather than the Ariel 7" full-width alloy hub of the HT5 and the roadsters. The one I knew in Oxfordshire I'm sure had the Ariel brake and all of the contemporary photos I've seen...

The original switched charge control was pretty poor and it wasn't uncommon for owners to swap the alternator coil pairings to increase the charge at low revs. This had the effect of boiling the battery on a longer run with the displaced acid eventually rotting out the battery support, the front par...

There isn't much in common between an HT and a road-going Ariel - the frame, forks, gearbox, swinging arm, back wheel, oil and petrol tanks are all special. I've only knowingly met one HT3 and that was in darkest Oxfordshire a very long time ago. I never really saw the point with the 350 weighing pr...

What voltage is the battery and do you know if a previous owner has fitted an electronic
regulator?

The original rectifier lived behind the drive-side tank badge. It's actually a bridge rectifier
and a little patience and a multimeter should show which if any of the diodes are
leaking.