If the slipping clutch setup is overworked by a dynamo problem, it can generate a lot of heat, which can cause the magneto to fail. Leaving everything to cool down, the magneto can then resume action. I had a problem some time ago when converting an aged dynamo to 12V caused the commutator segments ...

I don't think so, they are a bit larger, although I once had a BSA taper roller headrace outer ground down to fit an Ariel swingarm frame

The oil pump balls are 7/32", as Nev says a funny size. Sometimes the old balls can raise a lip in the metal around the seat, causing a new ball to not bed down correctly, check for this and also lap in with some Brasso/metal polish, but wash it off thoroughly before replacing the pump on the m...

I had a problem in the past with a VHA cylinder head used with a new alloy barrel, in that the top of the liner did not mate up with the cylinder head, probably due to excessive grinding in the past. I cured the problem by placing a thin copper gasket on top of the liner lip to fill the gap (anneale...

For the dynamo, use a piece of old inner tube cut to cover the brush end, overlapping the body/end cover gaps. For the magneto, ensure the entry point of the HT lead into the pickup is sealed, there are tight fitting sleeves to help this, but they may not be available at short notice. Perhaps a bit ...

I have just been informed that Derek, a mainstay of the Cardiff Branch since the 1950s, has passed away in the care home he was in residence at. He must have been one of, if not the sole, longest member of the club, being very active in the early days of the branch, when many runs between Cardiff an...

There are a number of WNG 350 pistons offered online, which have three compression rings instead of the two compression rings and an oil ring of later NH pistons. Using the WNG piston with the later type oil pump, with a larger feed plunger can give problems with too much oil reaching the combustion...

Hi Owen Great to hear you are still competing on an Ariel, I brought some spares from Derek Wing recently that had been supplied by Frank, as Derek had frequent contact with Frank in his earlier days, and was also supplied with technical data. He had asked if they could be offered to you if they wer...

Simon, if back to front, the taper on the arm would not fit the centre part

At a first glance, it looks like your lifter arm is for a side valve, which has the cable ferrule slot on the other side. I have a few lifter spares, if your are unable to source the right arm, I will check what I have.