One would expect not but:
[list=][*]a lot of civilian bikes were requisitioned for war use[/list]
[list=][*]Ariel probably had a big stock of oil pipes when war broke out[/list]
[list=][*]When bikes were serviced in the field, whatever spares were available would be used
- when someone restored a bike after the war they often wanted it to look better than a war department bike.
So what you have may not be pure specification, but history associated with your particular bike.