Hi, I’m new here and I’m new to the MTB scene. I live in Florida which has a lot of sand on the trails I live near and it collects everywhere. Most places I can clean easy and get it off but I was wondering if putting a little bit of finish line dry lube on the BB where the crank goes in, if it would help with keeping sand out. Is that not a good idea to lube this area or is it okay?
Grease is what you need in/around the bottom bracket area. It’s thicker than lube so it will stay in place better, and it prevents water from getting in places where it shouldn’t. The downside is grease is sticky and will attract sand. Wipe off all of the excess grease to avoid picking up a lot of grit.
I would NOT use any lubricant in that area as it may attract more sand than it does when dry. When I lived in Florida I used a cheap synthetic bristled paint brush to dry brush the area clean after every ride and followed up with some compressed air to blow remaining dust away. You must be very careful with the compressed air as not to force the sand into the bottom bracket. If you do not have a compressor i would just follow up the brushing with a thin rag to “floss” the area. Clean, inspect and lubricate your bottom bracket and crank arms often (of course the frequency depends on how much you ride). Be careful not to force water/sand into bottom bracket when washing bicycle. I hope this helps.