How do I know when my pinch brake calipers need to be replaced?

[jtreagan]

Bicycle repair newbie!

I've been fighting and fussing with the v-brakes on my wife's bike. (The linear pull variety.) Watching lots of videos, but still can't get it right. Most likely the problem is my clumsiness and ignorance. Those two problems will likely be solved over time and I'm sure I'll eventually get those calipers adjusted correctly. However, if they actually need replacing, how would I know that? Anyone care to educate me on this issue? Thanks!

[Jesper]

(07-31-2021, 02:19 PM)jtreagan Wrote:  Bicycle repair newbie!

"... with the v-brakes...sure I'll eventually get those calipers adjusted correctly."

Do you have photos? You mention "V" brakes (longer arm version of canti's/cantilever brakes), and caliper brakes (single/dual pivot; monoplanar/biplanar). Those are two different types so I am confused as to your reference. "V" brake arms mount on separate pivot studs to each fork blade and seat stay; calipers have a single mounting bolt at the bottom of the fork steerer/fork crown and seat stay bridge.
I'm sure you didn't need to educated there; but many folks without having a visual reference may get confused into thinking they are the same if reading about it and seeing those terms being used together.

My experience is primarily with calipers so someone with that knowledge should answer if yours are "V" brake canti's. I'll need to learn more also since I am building a cyclocross bike which require canti's; no idea what I need!

[ReapThaWhirlwind]

They hold up a long time. You only need to replace them if the internal spring is busted, or if you bend one of boss pins.

All the rest is getting the spacing and the adjustment screws right.

[jtreagan]

The springs don't look good at all (in my in-expert opinion) so that may be part of my problem. Amazon has a set of linear pull brakes for $16. Maybe I should go ahead and get them. Might solve some of my frustrations.

What's a "boss pin"?

@Jesper -- There are multiple types of pinch/v-brakes. This video starts out with a screen that has pics of each type. The video is pretty good, too. Mine are of the "linear-pull" variety. https://www.youtube.com/watch?v=XMa9UqY9obk