Originally Posted by
Wilfred Laurier
i am not sure if this is what you were implying but
4mm is tiny in many repects
but a pretty big increase in the distance between the brake pad and pivot
meaning it will almost definitely noticably crapify the brakes
The impact of the 4mm shoe movement depends on the type of brake and the original reach. On a single pivot caliper with a typical reach of about 50mm (older 27" bike) it's a difference of only 8%, so not exactly earth shaking. It makes more difference on dual pivot brakes because the pivots are lower, so the change is proportionately greater.
It would make the most difference on canti or V-brakes, but here it's closer to the pivot so leverage would increase.