Other Ariels in TV programmes I can remember:
Campion - Sweet Danger, starring Peter Davison, Brian Glover and Lysette Anthony. A black 1930's Ariel is seen quite often.
Miss Marple - Bertram's Hotel, starring Joan Hickson. The briefest of shots, Miss Marple crossing a road, a sidecar outfit pulls up at the crossing and it has an Ariel headlamp cowl, about all that can be seen of it.
The Avengers, starring Patrick McNee and Honor Blackman. A very early series 2 mono episode. Cathy Gale (Honor Blackman) is driving somewhere in a sports car being followed by a motorcycle. She stops at a transport café and when the rider follows her in she nips back out and rips the spark plug lead off his Ariel single before driving off. When you think about it, the episode was filmed in 1962 and the late 50's Ariel would only have been 3 to 6 years old.
If that doesn't qualify me for an anorak upgrade, I don't know what will....
1935 cammy Square, 1938 VB, brace of 1950 MkI Squares, 1959 MkII Square and several Ariel and Fleet pushbikes.