Originally Posted by
shelbyfv
I wouldn't go to any trouble to keep all bikes the same speed. It's not difficult to keep a couple of spare chains around. A disadvantage to 10 speed is that if you need shifters you will be limited to lower level components unless you can find NOS.
I have several sets of 10-speed wheels that rotate among 3 different bikes. Nice to be able to swap different tire and gear set ups from bike to bike.