i'm sure i have read or seen somewhere? that the TA has "skyway" on the sticker and the TA XL has "skyway ta" on the sticker.
there were two sizes of the ta.
although the XL version was introduced later than the original.
i can't prove my explanation further.
further debating and investigation may ensue?
get your tape measures out boys,
BUT don't bother unless you know the original stickers for your frame!!!
maybe the tale of the tape will shed some light on this matter?
?