U-brake conversion from up pull to side pull (like bmx front brake)

Question

I have an old steel Belgian bike from the 80s (I believe) which I am trying to restore to make it my daily commuter. I have to replace many things and every time I encounter that the bike is far away from every standard I have worked with before, i.e. stronglight cranks with 23mm. It also came with U-brakes. The problem with them is that I cannot add a front rack as the cable going down (to pull from above) interacts with it. It is the common cantilever style of a cable going to a triangle where another cable goes to the brake arms (sorry about this pic, can add better later).

Yesterday I worked on a conversion to make them side pull by using parts I have at home from other brakes (will add picture eventually if needed) but I realised one of the arms bent a bit towards inside while applying a lot of force and I don't want to stress them like that. Today while researching to buy new arms I realized that there are these little things that would be the ideal thing to make a conversion but I cannot find them anywhere online. Anyone has an idea of how they are called and/or where to find them?

Answer 1

The cable anchoring bit is called a 'knarp.' The part with the barrel adjuster and housing stop on it doesn't really have a universal name for this application. Knarps are fairly universal because they all give the same OD of the round part as a standard MTB/BMX brake cable. They're used for a few different applications on bikes, mostly BMX. You can get them standalone from companies like Odyssey. The housing stop part is usually considered a little more specific to each brake, as the different brakes do different things to integrate them neatly.

Middle to upper end BMX brakes usually come out of the box with the parts needed to be set up sidepull, and the companies that make them will typically also sell complete replacement hardware sets. If the bike has conventional 990-style U-brake mounts (all or most MTBs that took u-brakes did - this is the Dia-compe-originated standard that Shimano and others also used), just getting such a brake is probably the move here. If it doesn't have 990 mounts you might be in trouble.