Shimano Brake Caliper Bolts - Safety Retention?
 

I just received a custom built bike with GRX components and among other issues have noticed that the builder failed to use any (front) or incorrect (rear) hardware to to prevent the caliper bolts from coming loose from the frame/caliper and falling out.

At least on the front it looks like they used the Shimano supplied bolts with loctite applied. However, the anti-rotation clips for the bolt head were not installed.

On the rear they used what appears to be standard stainless allen head bolts and didn't even use any lock washers or loctite!

So what is the general practice in using specified retention components? Is loctite sufficient or should there be a secondary retention such as a clip or a cotter to keep the parts from falling out?

My used R3 the same way and the bolt head hex had seen better days.
I replaced both the bolts and clips.
performance Bike had the parts in stock.

Barry

Many thousands (millions?) of bikes have no threadlocking compound or anti rotation clips on their caliper bolts and these bolts are still tight. I feel this stuff is more about the person who puts it together and the other guy who takes over the maintenance. if they both do their jobs loose bolts are a very rare issue. A lot of this stuff, thread locking and tabbed fasteners is about the lowest grade of service abilities and liability lawyers. Andy

This and just keep an eye on them. They won't unwind all the way with out you noticing.
How experienced was the mech?

I actually remove the thread locking compound on my caliper bolts...or at least dilute it with grease or oil when I install them. And I don't use the plastic retainers, either. Not because I'm a "tough guy", but because that stuff just doesn't seem to be necessary, and it's annoying to me, one who is always (by choice) fiddling with my bikes, swapping tires and wheels to try different combinations on different bikes, or moving one set of brakes from one bike to the other, etc. Properly torqued, a caliper bolt won't back out on its own.

I agree about the lawyers to a certain extent. However, my engineering background tells me that there should be at least one method of retention to prevent a worst case scenario. In my case the rear bolts had none! The Shimano bolts come with Loctite applied and this should be enough to keep the bolts from falling out. The clips and pins are the second level protection to satisfy the lawyers.

As Andy noted, spontaneous loosening of properly torqued bolts is very rare. However, a small tube of Blue (Grade 242) Loctite is readily available from any hardware, auto parts or big box home store and is cheap. It's an easy DIY project if you are concerned.

Did the bicycle come with or call out all the necessary hardware that was not installed at some point, & get deep sixxed during the assembly? If that is the case, I'd contact them to make it right.

*If I suspect a bolt or nut to become a problem keeping its' tension & it's not hidden by other parts, I'll put a paint mark going from somewhere on the hardware to the nearest point of the part. If it walks any, I'll be able to have evidence that it needs to be addressed. I've had it happen & the extremely extra effort in adding that paint marking really made it worth it.

I'd argue that bolts connections on a bicycle that require thread locker to stay tight aren't properly designed (or assembled).

In my experience:
I always use anti-seize on the threads, removing any factory-supplied thread locker.
Yet to have a brake bolt come loose.

Of course, it is possible. And yes, some people don't notice those things, until they completely fall off (sometimes not even then). Suppose that those plastic clips are a good idea for such cases (and the main reason I don't throw them away).

Brake Bolts vs Dork disk
 

A correctly maintained bike may not require a dork disk.
"Most" of the people that frequent a hobbyist forum such as this understand purpose of the disk and risk/benefit associated with it.

Brake bolt retention hardware is similar in that we get to make our own decision.

I chose to purchase Shimano replacement bolts and retention hardware.
I've never been laughed at for having it, .......dork disk, well that's another matter!
YMMV

Barry

It should have come with the proper hardware. They use Syntace mounts with a 15mm thickness so they should have had the correct Shimano bolts for the rear caliper. I am assuming that the mounting plate to caliper pin got lost during assembly at some point. Yes, I will be going back to the builder for the missing hardware.

BTW, do the Shimano GRX calipers come with the mounting plates attached or are these bike and frame specific and selected at installation time? The rear mounting plate on mine says "R160 FM1.1"