Both Dunlop and Michelin tire fitment charts show the 2000 and up B6 to use a 120/60 front. I would assume the front rim to be 3.5 or 3.0 inches wide. Either way, the 120 front is a better size as you will have the best tire choices as all current sport bikes run that size front.
You should have the size--17x3.5 ect --stamped on your 2001 B6 wheel. Check your stock front tire, if this is correct, your stock profile- 120/60- is slightly shorter than the B12 profile- 120/70.
This will not matter, the 3.5 in front B12 wheel is a perfect match for a 120 front. Both 120/60 and 120/70 are available from all tire manufacturers.
Good Luck, ed.
2005 GSF1200SZ
1983 GS750ED