stock EFE wheel sizes

Hi peeps,
today i swapped the gold wheels for black ones in the EFE. As far as i know, it came from the factory with the gold ones. The black ones came from the EFE i bought from FBJ five years ago.
One thing i noticed (apart from the colour difference) is that the black ones are a little bit wider, front 16X2,75 (gold one is 16X2,50) and rear 17X3,50 (gold is 17X3,00).
Why is this? Did the EFE have narrower wheels on some markets? Or is the difference age-related? Are all the gold wheels narrower than the black ones, or is this a coincidence?
today i swapped the gold wheels for black ones in the EFE. As far as i know, it came from the factory with the gold ones. The black ones came from the EFE i bought from FBJ five years ago.
One thing i noticed (apart from the colour difference) is that the black ones are a little bit wider, front 16X2,75 (gold one is 16X2,50) and rear 17X3,50 (gold is 17X3,00).
Why is this? Did the EFE have narrower wheels on some markets? Or is the difference age-related? Are all the gold wheels narrower than the black ones, or is this a coincidence?