I bolted(Thorx) the eyebrows on a couple of months ago on a whim. I like the look, and seeing that strip of chrome running along the sides as you look down on the tank is pretty cool in my book.
Now....Keith, to answer your question..."Sonny"(and if I can still get the "old" grey matter workin' correctly....[note: to self...be sure to stock up on the Genkoba])
....
The "mouth-organ"(said to resemble a harmonica) tank badge, which Dennis here prefers, were originally on the mid-50s to the 1965 model year Triumphs.
In 1966, Triumph went to the "eyebrow" badge, which looks similarly to the new badges that I put on my bike.
In 1968, I think it was, Triumph went to a slightly smaller and abbreviated version of the "eyebrow".
Cheers,
Dwight
(if the "old" cranium has let me down, I'm sure somebody here will correct me)
