Ah, that's what the noise is

For quite some months now, my bike has been making strange creaking and cracking noises, especially if I bounce up and down a bit.  It has gradually been getting louder and I had been trying desperately to track it down.  Maybe the bottom bracket?  Still there after that needed replacing last year.  Perhaps the headset?  No, replacing it didn't help. The saddle or saddle pen?  Stand up and it still does it. Maybe it was in the rear suspension, but taking that out and carefully cleaning all the joints didn't help.  So finally I had a really good look today and the slightly raised scratch under the bottom bracket that I hadn't paid much attention to earlier was indeed a nasty crack that was actually quite scary when examined closely. So now the mystery is solved and it is just a matter of working out what to about it.

Strangely enough, the reason that I finally found this was that the bike was also otherwise misbehaving itself.  A couple of weeks ago, all of a sudden the rear brake lost pressure.  However, after leaving it overnight with the lever bound up, it seemed to recover nicely (as promised by the wisdom of the internet). Then last week I was out with the club and the rear brake completely lost pressure, dropping a pad in the process. I took it into my LBS and they bled it for me, so I was expecting no problems today.  However, after only a few minutes in the woods today, a pad fell out again.  After a bit of a search I found the pad and refitted it (astonishing patience of the others whilst they waited for me to faff around with it), but then it fell out again after only a short distance, the very next time I bounced over a root. So clearly a somewhat bigger problem than just a bit of air in the cable.

When mountain bikes are working properly they are wonderful machines, but not on days like today.