My bike developed a rattle at the front end, starting intermittently, but quickly becoming continuous - in the sense that every time we hit a bump it rattled. I traced this to the brake caliper mounting bracket.
This was dismantled, the tattered o-rings - one was in fact torn – replaced and a copper washer put in at the top end of the pin. 500 km later the situation was as bad as ever.
Another dismantle and this time a thin wire was wound around the pin to supplement the washer that looked a bit crushed. A thicker split pin was also inserted.
500km later, bad as ever!
Now I’m back home - oh, forgot to mention that this all happened on a 4,500km road trip that I’ve mentioned elsewhere. I searched the forum and discovered that this is not an uncommon problem.
I dismantled everything, yet again and did a few measurements. The holes in the mounting arm were clearly ovalled and the pin itself worn - 9.7 vs a nominal 10mm. The o-rings, replaced only 1,000km ago were tattered.
I had a spare bracket and measured it up, not that this was necessary because there was no play to talk of, but the hole was round and the pin measured 10mm. There were also no shims in this one as compared to the “old” one which was shimmed to a total of 0.15mm.
Hopefully problem solved.. I just worry now if the replacement bracket will go the way of the original on Africa’s roads.