I run a 130/70 in the front. I have used a 180 rear, doesn't feel any different than a 170. I only tried it because it was cheaper than a 170 at the time. The reason the 130 doesn't rub is it's a 70 aspect ratio. Only 3mm taller than a 110/80.
Steelheart- '03 Speedmaster Black/Yellow
The Hayabusa Killa
16" Shorties/140 mains/Airbox drilled
Procom CDI
"There is no cure for Celibacy. But we can treat the symptoms."