nes i had to do this to an old not so nice frame, the outer hole in the bridge is 6mm, the inside is more like 10 thats if you fitting a brake like this style of bolt?,
it can be awkward to drill the inside because the seat stay gets in the way, if you are unsure i would take it to bike boutique
nes i had to do this to an old not so nice frame, the outer hole in the bridge is 6mm, the inside is more like 10 thats if you fitting a brake like this style of bolt?,
it can be awkward to drill the inside because the seat stay gets in the way, if you are unsure i would take it to bike boutique