Brake overhaul - do I really need rebuild kits?

[Roostabunny]

Hey all.

Planning to get my brakes working better. They are currently reliable and stop fine, but they require more effort and provide less modulation than I think they should.

I'm going to do stainless steel lines, and I'm pretty sure I should rebuild the calipers, but I have two questions.

1.) Do I really need caliper rebuild kits, or can I just clean, lube & reassemble?

2.) Same question for the master cylinders.

Thanks!

 

[spyug]

It really depends on what you find inside. I've done at least a dozen in the last 3 or 4 years and didn't find any that needed "rebuild" kits. Having said that, however, I've had at least 4 that required new pistons.

The piston surfaces that fit in the bores are "hard chromed" to resist rusting. Despite this many end up with cracks in the chrome that allows water to penetrate and create rust. The chrome can flake off exposing the steel which can then rust. In some severe cases the rusting can also adhere to the wall of the bore effectively jamming the piston ( usually when the bike has sat for a length of time).

If you find a piston with pitting or the chrome cracking or flaking, you should replace it as its an accident waiting to happen.

As far as dust seals and the piston seals they can last a long time if properly looked after but for peace of mind, especially if the calipers have not been seviced in eons, best to change them out too.

SS lines will make a huge difference in braking power, feel and fade and its the first mod I do to my bikes if they're no so equipped.

If there is anything on a bike not to cheapen out on its brakes (after tires). Its good to get into the habit of changing out the fluid too and I recommend at the start of every season as part of the "spring tune up". If you invest in a Mity Vac it only takes a few minutes and it will go a long way to keeping your brakes in good order.

Peel open those calipers and masters and let us know what you find.

Cheers,
Spyug