Are the springs on disc brake pads cross compatible?

[Manc33]

I have non-genuine Avid BB7 sintered brake pads on my bike at the moment and it's time to replace both pairs.

Can I reuse the springs from my current (non-genuine) brake pads, on the new (genuine) pads?

If they fit one they must fit the other, right?

[Cugel]

I have non-genuine Avid BB7 sintered brake pads on my bike at the moment and it's time to replace both pairs.

Can I reuse the springs from my current (non-genuine) brake pads, on the new (genuine) pads?

If they fit one they must fit the other, right?

There's two aspects to those springs that are significant: the exact shape of the spring; it's strength in pressing the brake pads apart and on to the brake's pistons.

Although a 3rd party brake pad may be superficially the same size and shape as the pukka pads, even small differences in the shape of the brake pad itself might mean that a spring from another, different maker will not fit well. However, having used a couple of 3rd party pads for Shimano disc brakes (the Shimano pads, like much else imported, are in short supply just now) I can say that the spring shape of both pads (3rd party and Shimano) are the same and fit well on either type of pad.

However, the spring strength of some 3rd party pads is reputed to be too strong, when one reads customer reviews of such pads. The 3rd party springs can be quite a lot stronger and can push the pistons back to such a degree that it causes some buyers to have a leakage of the hydraulic oil . Personally I suspect that this is really because there's a weak spot in the hydraulics that allows a leak to happen when the system's pressure in increased a bit by piston push-back from the pad-springs. Still, why take the risk?

So, I always use the Shimano springs with new 3rd party brake pads, as they fit around the pad material well and offer the same pressure on the pistons as the brake hydraulics "expect". It may or may not be the same case with your Avids. You can only try them to see.

Cugel

[Manc33]

Still, why take the risk?

Because a pair of pads is £6 without springs but £17 with.

I probably would buy the springs too (since it's still going to be cheaper doing it that way) but I can't find anywhere selling BB7 springs. Elixir yes, but not Juicy/BB7.

Edit: FTLOG there are ones with springs, but because "BB7" isn't in the title (but "Juicy" is) I didn't find them... too late now.

Why is the same seller selling them at £5.99 without springs but £5.49 with springs. Exact same photo in each listing.

How are the same pads £5.49 at one place but £16.99 at another.

[Marcus Aurelius]

The springs aren’t strictly necessary. I have some very nice pads ( with heat sinks ) for my Magura / Bianchi brakes, that don’t come with springs, and they function perfectly well without them.

[NickJP]

The springs aren’t strictly necessary. I have some very nice pads ( with heat sinks ) for my Magura / Bianchi brakes, that don’t come with springs, and they function perfectly well without them.

That's probably because some Magura calipers use magnetic pads and pistons rather than springs to retract the pads. If the caliper is designed for use with springs, then the pads won't retract properly without them.

[Manc33]

After all this I think I probably do have genuine pads already in my calipers.

The cheap pads I bought actually went on a pair of road BB7 calipers, I sold some time ago.

Since I was selling them, I wanted them to have nearly new pads, so they had those (almost) new pads fitted.

The pads on my current MTB calipers are the ones that came with them, in 2018.

I wondered why I needed new pads... they are from 4 years back! Probably less than 1mm left on the front now.

[hoogerbooger]

This looks a suitably relavent previous post.

Picture below is from TRP spyre. Can you see the daylight between the piston and pad !:

( derr!! Not sure why 2 copies of picci. Look at lower piston)

And bottom is the spring taken out next to a previous Spring:

Both springs are from non-shimano (or TRP) copies. The wider spring on the left appears wrongly shaped at the bend leading to it flaring out more & being 4mm wider at the spring ends....and being sort of usable but rubbish. Have now used the previous spring on the right.