joebristol – Member
…Cables are fine and calipers aren’t corroded…
Flex is the enemy of cable brakes and most of it is found in the cable outers which are usually spiral wound and compress under pressure – using up braking force.
So what looks like a good cable can be crap under the pretty covering, especially OEM. I suggest replacing the outers with a top quality compressionless set. This is the biggest improvement you can make in a cable brake IMO.
Another place for flex is where your brake pads touch the rim. If it is the outer edge and the rim is worn, you can get a wee bit of flex there too, so it’s best to set the brakes closer to the inner part where the box section of the rim is. It would be better to change the rim though in that case. (Most people never get their rims worn enough for this to be a problem)
An eyeball on your brake system while squeezing the brake as hard as you can will show up any obvious problems – if you can see it flex, that’s a problem to be sorted.
Thus if the callipers are moving freely and not observably flexing under pressure, they’re probably ok. If they flex, get stiffer brakes.
All this is assuming your rims and pads are clean and oil free of course.