Bicycle brake caliper screw

chris_n

Note that the blue stuff is a type of low strength thread locker, putting a normal screw / bolt in there without some form of threadlock is unlikely to be successful in the long term. 

Spinybif

Halfords & Decathlon both sell spare nuts and bolts.  Take the bike down and ask them - they are usually happy to advise

FreeBear

dwhl said: this is the photo of the calliper and the screw. You’re right 8mm…. Likely the M3 then?

Looks more like M4 to me.

ThisIsWeird

Crude, but I'd still go for three:

It isn't really tapered, is it?!

FreeBear

ThisIsWeird said:

Crude, but I'd still go for three:

It isn't really tapered, is it?!

Thread pitch is too coarse for M3.

Just checked the screw on a pair of brakes here - M4x0.75mm

ThisIsWeird

I stand corrected.

Again.

daivid

If you haven’t sorted it yet OP ring round any independent bike shops you have nearby. A decent bike shop will have drawers of setscrews etc for when they do services, you can also buy service kits for good quality brakes, theres no brand name visible in your photo but if they are a named brand you could use that to help your search. Isla use quality components on all their bikes so far as I know, though the group sets do vary across the range and by year of manufacture.