TRP Spyre cable disc brakes ...... Part missing?

[Donger]

I have just ordered and received two sets of Swissstop brake pads for my TRP Spyre cable operated disc brakes, but looking at videos and pictures online, a small part appears to be absent from the brakes currently on my bike.
In the picture below, you can see what the pad retaining pin is supposed to look like .... complete with a 28.5mm clip at one end:


I was just about to get started on undoing the retaining pin with a small hex tool, when I noticed that the clip is not there. This begs three questions.....
(1) Could this account for why my front brake had suddenly lost effectiveness, still not gripping even when the cable was tightened as far as I could get it to go?
(2) Did the absence of this clip make it dangerous?
(3) The rear brake seems to be working perfectly, but is also lacking the 28.5mm clip. How do these just disappear? This is the first time I have ever even considered adjusting or replacing parts on disc brakes, so their absence is certainly not down to anything I have done. Have I been unknowingly riding in the hills on a death trap .... an accident waiting to happen?

Any thoughts/experience of this? Looks like I'll have to buy two new retaining pins (£4 each, so no big deal) to get hold of the right 28.5mm clips. Quite bizarre that they are not there though.

 

[Slick]

Does the clip just not come with the pads?

They just disappear when someone pulls the pads and lose the circlip, no big deal.

 

[Donger]

Does the clip just not come with the pads?

They just disappear when someone pulls the pads and lose the circlip, no big deal.

No, the pads come with the spring that separates them. The clip I'm talking about is the one on the retaining pin, as shown in the photo. ... the "circlip" that you are referring to, I assume. As the retaining pin has a thread to it at one end, do you think that keeps the pads firmly in place even if the circlip pops off the other end?

 

[si_c]

The little clip is intended to stop the pad retaining bolt from coming out. If it's done up tightly enough then it's absence is not a concern.

I ran my Spyres for 18 months with it missing after I dropped in on the grass in the dark in a moment of stupidity. Not once did the pads subsequently become loose.

 

[Donger]

Thanks @si_c. .... Quite reassuring. I guess the thread at one end of the retaining pin provides the stability, and the circlip may be a belt-and-braces operation. Some other brakes seem to just have a cotter pin instead of a threaded pin.

 

[I like Skol]

www.cyclechat.net/threads/shimano-m785-r785-brake-pad-security-pin-spring-clip-y8jz98010.224990

 

[Donger]

www.cyclechat.net/threads/shimano-m785-r785-brake-pad-security-pin-spring-clip-y8jz98010.224990

Thanks for that, @I like Skol. Seems we are of like mind. If they think it needs a clip, it doesn't feel quite right not having one ...... though the comments back at that time confirm the general consensus that the screw thread really should be sufficient.

In my case, I guess the clips went missing during maintenance at the LBS. Had it only been one of them, I would have put it down to blasting it off with a jet wash.

 

[figbat]

The clip is like having someone follow you around holding your trousers up, even though you have a belt and braces already on. The primary factor is the pin itself - it screws into a thread and, if tight enough, should stay put. The first layer of defence is the threadlock that appears to be on the thread - that pin is not coming undone if fitted correctly. The clip is there in case the threadlock fails and in case the pin wasn't tightened correctly.

One is missing from my Spyres - not had a problem so far.

 

[Donger]

Thanks @figbat .

 

[Ajax Bay]

The clip is like having someone follow you around holding your trousers up, even though you have a belt and braces already on.

Well I suggest that the clip is a 'second fastening' of the pin, the first being the pin securely screwed into the caliper side. So it's more like having a belt as well as braces to hold up one's trousers.
In relevant industries, the primary mitigation to avoid 'dropped objects' (from height) is to have a secondary fastening/retention device in case the primary one fails. Given the level of hazard/consequences if the pin came out, this is good engineering practice/design on behalf of TRP/Tektro.
And for the OP: the pads come without a pin of any kind: I guess they expect the rider to use the one the brakes came with. Sometimes you get a simple split pin, which might fit through the threaded hole and then allow the ends to be splayed/bent outwards.