Originally Posted by Shiznaz
but carrying an extra cassette and the tools required to install it just opens up the gates for carrying extra BB's and chainrings and stuff.
I'd carry at least the tool to get the cassette lockring off, in case you break a right side spoke on the rear. You can probably use the chain and your bike as a chainwhip somehow. I seem to remember seeing a replacement spoke that was made of flexible material...maybe you could use something like that without taking off the cassette. What are you going to run for wheels?