Tire clearance depends on which tire and rim you’re using. I know that several local riders are using the latest wide KH rim with Gazz 3.0 tires, and there’s not much clearance. It’s important to keep the wheel true so that the tire doesn’t rub.
Speaking of MUni, has anyone here played with shorter length cranks? No, not long 150s. I’ve been toying with 137s on my KH24, and I really like them. I would consider shorter if I had a brake. The only downside I’ve noticed is that steep downhills require a greater commitment. People say longer cranks give you more leverage for climbing; my experience is that longer than 137 mm cranks feel like more work to climb with. And I feel so much speedier on flat sections.