i have a friend out in socal who recently dimpled the inside of a steel fork of a mid level bridgestone about 1-2mm per fork blade to gain enough clearance to go a up a tire size. frame already had enough space on the chainstays. i'm curious to ask any frame builders : do you think this would have any adverse effect or since it's steel and the dimple was 1-2mm it not really an issue? not sure i'd be open to doing something like this in the future but it is interesting. he went from 1.8" width tires to 2.3". i've seen people dimple chainstays but i hadn't heard of fork blades - thanks for you feedback !