chain back up
used to carry a spare bike to kit chain because I had seen some early TS kits crap chains.
When it became obvious you need to put high quality o ring chains on the bikes, I don't hear much chain noise anymore.
What I have learned on the bike't chains:
there is no substitute for running snow on the chains and keeping them lubed, cool and lubed and they will LAST
buy good chains, check and read up on tensile strength, you pay more you play more with peace of mind.
carry extra master link and link and GOOD chain breaker
there is about 273 different masterlink sizes for 520 o ring chain, I have a 30 year accumulation of masterlinks that won't fit a single chain made. So when you buy a good chain, buy several extra masterlinks
when in doubt a looser chain beats the heck out of a tight chain, nothing good can result from a tight chain. You will find snow conditions that form a thin layer of ice on the roller and will tighten a chain a lot...........easy enough to snap a chain if the chain was too tight from the start.