5 color flames, 2 1/8" diam., lights up at night. $4 extra for custom internal thread. By golly, I LIKE IT! And I think I could make it work on a bike.
Not period correct. But neat all the same. http://www.flameball.com/
They do have a 1 7/8" diam. "Eight ball series", and some pearl. Who was making those period correct ones for bikes? The swirl ones.