Life of a waxed chain

[weaponsgrade]

I've been riding with waxed chains on some of my bikes and thought I'd report on some findings. One of the things that's been interesting is how the need to rewax seems to manifest itself in a loud creaking noise when in a low gear. I had some low gear creaking noises on one of my bikes. I pulled the hub apart and couldn't see anything amiss. Bearings felt fine, no cracks, etc. It didn't yet occur to me that the chain needed a rewax because the creaking only happened when I was in a low gear and shifts seemed fine. I didn't have time to put everything back together and I set the wheel aside for a bit while I got some rides in on my other bikes. I then experienced the exact same sound on my other bikes - creaking, but only in low gear. I rewaxed all the chains and now all is good. Here's how many miles I got out of each bike:

Bike 1: 270mi
Bike 2: 120mi
Bike 3: 426mi

Bikes 1 and 2 are mountain bikes. Bikes 1 and 2 had some riding in some damp conditions. I seem to recall riding bike 1 in more damp conditions than bike 2, though bike 2 was subjected to some pounding rain while mounted to the roof of my car. Bike 3 is a gravel bike that saw a mix of mostly dry road and dirt conditions.