There's a good thread going on in the Bicycle Mechanics forum
Finding tube leak
I'd like to know your ideas (and experience) on how to find a leak in the tube during a randonnee, at night, in the rain, after a few hundred km's...
Until now, luckily, all my flats didn't stop me from riding (none was during a randonnee.)
They were slow leaks, and didn't prevent me from getting home, and patching them calmly.