Ideally, I should be using a 15" bike, and the smallest ChangeBike 650B is 17".
So if you can, do go for the more typical stem lengths.

That said, the bike has a long top tube (modern mtb style) and short stems are typically used as well.


Steering reaction is certainly fast with the 45mm stem on the road, but one gets used to it after hopping on the bike for a while.
However, on trails, the more nimble handling comes into its own (and is very welcome )