Ariel Owners Motorcycle Club

On the drive side of the crank cases these are stamped with a ‘R’. Is there reason for this? Rigid frame? Any explanation?

Oh, that 'R'! No idea, all sorts of things get added by people who rebuild engines etc. My MKII add "rebuilt be Manhindra Singh" scratched inside the timing cover, presumably so that I knew who to blame for all the bodges perpetrated.

I'm sure this has come up before but at the moment I can't find the thread.

I have a pair of crankcases with what looks to be the same letter 'R' but
stamped inside the cam chest as well:

A further though: Both CH and CE prefixes applied to all 500s - does the 'R' denote
a roller bearing bottom end rather than a ball bearing. My cases certainly has rollers
and steel flywheels.

Hello Will, interesting! I’am quite sure this stamping is a genuine Ariel one. The size and form of the ‘R’ is the exactly same as on my 1940 VG cases. But what does it stand for?

ok, another mystery!

will_curry wrote: ↑Sat Jan 06, 2024 7:30 pm A further though: Both CH and CE prefixes applied to all 500s - does the 'R' denote
a roller bearing bottom end rather than a ball bearing. My cases certainly has rollers
and steel flywheels.

According to the parts list from Draganfly, the VG is fitted with three ball bearings in the same way as the 350 NG, NH etc… So it looks the ‘R’ does not denote roller bearing. I replaced all the bearings. The ones who came out where also ball bearings.

Ah! going anal with analising I suspect these letters are builders marks.
my 1940 VH engine also has the 'R' on the DS and inside near the camshaft bush.
few years ago I spotted a '39 VB also with a 'R' stamped.
so there goes the 'roller' theory.
One thing is clear; he (or she?) was not looking how the stamp was going to end up on the alloy

numbers are also used ?
my HS MkIII had a small '3' stamped on the TS crankcase.
picture shows not my HS engine but from the net, I think it's also in our knowledgebase
maybe to tell folks further down the production line that this engine should recieve the MkIII camshaft ?
I wonder if the MkI had a '1' stamped there as I am only guessing !

I'll have to look at my HS tomorrow.

Taking my 'sensible' hat off, I did wonder when the 'O' turned up whether the
next would be 'G', then an 'E' and finally another 'R' and the offer of a cup of
tea at Draganfly or an embossed membership card to the proud owner.

That certainly deserves a cup of tea Will, That made me larf it did.
Looks like the letters may well be something from the factory, could be an inspector, builder or testers mark. In the despatch books there is one that lists the name of the person that erected or assembled each bike covering about 5,000 of the W/NG during 1943. There are eleven names, perhaps a couple more as personnel change. I would not have thought that such a person would be identified by a single letter as it is too likely that there would be more than one with the same initial to their family name, in those days I very much doubt that they would use their given name. When such systems are used, usually inspectors stamp, it is with a number. Given the existence of an erectors book for a small batch of bikes it is most likely that all erections would be listed in a books. The type of main bearings fitted could be discerned from the model type anyway. I must inspect some crankcases.......