We have a Boss Stealth 26" men's mountain bike with Zoom brand disc brakes.

The disc brake pads are worn and need replacing, the problem is finding a workshop who can fit them as apparently it is a budget bike and hard to get the brake pads. Is it possible to fit another make of caliper which are readily available on ebay?

Both front and rear rotors are 160mm, or are the sizes from disc to frame bracket different?

  • 2
    Can you show us a photo of the present disc pads and tell us the exact model of your brakes (or also a photo)? There are not that many types even though some are more common than other. Please note that even two different brakes from the same brand may use a different type of pads. May 15, 2020 at 19:26
  • 1
    It sounds like you don't want new calipers or disks, you want new pads. May 15, 2020 at 19:59
  • need discs but hard to get them fitted as i'm not sure how to fit them or the size so thought it might be easier to fit a new set of calipers May 15, 2020 at 20:03
  • Vladimir F i will get some photos tomorrow May 15, 2020 at 20:04
  • 1
    for disc it should be pads sorry for terminology May 16, 2020 at 9:26

4 Answers 4


Googling about suggests that the pads look like this:

enter image description here

These are listed as "Zoom DB280 DB550 DB450 DB350" compatible, and have a diameter of 18.5mm in the main, and the total length is 23mm.

Your best option is to remove one set of pads from the bike, (put a block in their place) and compare the pads with pictures. You'll find the right ones if you look hard.

Then make a decision whether you want to spend money on replacement pads, or choose a replacement caliper.

While searching I noted that the Zoom brake is not a quality brake and seems to have spend more on anodising than function. If the brakes weren't working well for you then complete caliper replacement is feasible.

Zoom disk brakes only support 160mm rotors, and you have to match the frame mount if you change to another brand.

  • that's the ones i was looking at May 16, 2020 at 9:29

If you cannot find replacement pads, many cheap off brand disk brakes use BB3 pads, have a look and see if they are the same. Changing the yourself is straight forward enough. Sometimes its as cheap and easier to replace the caliper, especially if paying a mechanic to source hard to find replacement pads. If you do, get one that is major brand, or at least takes major brand pads.

If you want to do it yourself and cannot find pads, there are two mountings for calipers, IS and Post. Generally buying same style caliper as you already have makes it a simple replacement. Adapters will probably cost more than a cheap caliper.

Disks come in two mounting standards as well. 6 bolt and center lock. If you want to replace the disk you will need the get the same type.


If the brakes are hydraulic I would not recommend replacing the calipers without replacing the levers as well.

There are two issues of compatibility. The first is that different manufacturers use different 'leverage ratios' which is set by the relative cross section areas of the lever and caliper pistons.

The seconds is that different manufacturers use different hydraulic fluids. Even systems that use mineral old use different formulations.

if you replace both levers and calipers you will be sure that you have a braking system that works properly.

  • not hydraulic brakes May 16, 2020 at 9:29

thanks for the help, i have removed the brake caliper from the bike and taken out the pads the pads are stamped with zoom 5 which are available on ebay, nothing wrong with the caliper or rotor also found out how to adjust the disc

happy cycling everyone

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