A friend has a couple of directional tires that are 5.00 x 16. They look just like the 6.00 x 16 WWII tires that would go on a Jeep but they are 5 x 16. XA? XA desert tires? Or are they for your grandmas rototiller?
The fall 2002 edition of the Antique Motorcycle shows a picture of a Harley TA. An experimental Knucklehead shaft drive trike built for the Canadian military, don't know the size but they are definatly directional....jb