Originally Posted by bastimentos
Please bear with me if it is a stupid question, but I tend to think of the F800GS as BMW's attempt to make a GS that is a lighter, and more capable machine offroad than its big brother - while still retaining civilised road manners and pillion comfort.
Maybe that's not what they were going for and I've misinterpreted it, but say they were aiming for this - why did they go with the 17/21 wheel combo over an 18/21 that has seen action in offroad oriented bikes such as KTM's and the HP2E to good effect?
I could be wrong, but I think the reason for 17" rim is that 17" is pretty much an industry standard these days for dirt, sport and ADV bikes. There are more tire choices for 17" rims and tire availability is not so much of an issue (specially in scenarios when there aren't too many bike shops around).
Currently - '15 Versys 1000, '15 KTM Duke 390, '09 Daytona (track only) Previously - '13 Multistrada, '13 F800GS, '13 MV F3, '10 S1000RR...and many more.