Yep, I thought about it later on! I came back to fix my post and it was already mentioned.
'91 had blue tubes aswell, though. Measurements at least for a 250 through '02 are '90-41mm, '91-'95-43mm (regardless of color) '96-'01-46mm and '02 was 48mm. I
THINK the 500 was the same, except it had 43mm '91 -
'96 and ran 46mm from
'97 - '04. 500's never had 48mm. Triple trees changed in '92 on 125/250's because of a different steering stem and bearing change. 500's still ran the pre '91 bearings through '04.