How's that? You can almost completely adjust them, there are spacers on the blocks and you can adjust the brakes a lot, don't think there will be a problem cause in that case the same problem would be there with fitting modern canti's on these kind of frames.
Yes canti's have same problem, atleast me and few other guys who have built vintage crossers, modern canti's you can mod with bendig the spirng, i don't know if it works with v-brakes.
I doubt if modern brakes will work on this, i had similiar cross trophy and brakes was pain in the ass, old ones have 55mm between the brake bosses and moderns have 80mm so there might be problem to fit those new brakes.
Well rear brake stopped working after first round and there is only about two mm between chainstays and tyre so it didn't take long that it was full of mud. Had some bad luck, two flats so didn't finish but it was nice track and had fun.
Yes canti's have same problem, atleast me and few other guys who have built vintage crossers, modern canti's you can mod with bendig the spirng, i don't know if it works with v-brakes.