Originally Posted by Drunk_Uncle
Woody, the standard 1190 has the same sizes according to Cycle World as the Water Boxer, 120/70-19 and 170/60-17. Now that two bikes and possibly more in the future are carrying this size, more tire options may become available.
I know Mitas makes two tubeless tires in the traditional 19/17 tire sizes. Don't know if those will work on the new wider rims of BMW and KTM.
Yes the 1190 and the R1200GSW have the same tire's, and front rim sizes, the 1190 has a 5 x 17, and the 1200 has a 4.5 x 17. We don't recommend any tire's smaller than the 120/70-19 on the front, and 160/70-17 on the rear on the BMW, and 170/60-17 on the rear of the KTM.
If you want to run the older 110/80-19, and 150/70-17 tire's, we can build a set of wheel's using 19 x 2.5 F, and 17 x 4.25 R.
If you have more specific questions, you can email us at firstname.lastname@example.org