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Lately, after my normal wash & lube routine, I've been squirting a little Teflon lube into the bottom bracket hub. I do so without dissembling by inserting the lube straw into the hub crevice. Is this advisable or a bad idea?

From what I can tell it seems to help prevent creaking, but maybe that's in my head. For what its worth I commute and ride often and live in the PNW (read: wetter than usual conditions).

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  • Are you using a conventional sealed bearing bottom bracket or some pressfit system or what?
    – Batman
    Sep 13, 2015 at 1:05
  • @Batman I'm actually not sure. The bike in question is a 2012 Masi CX (s21.postimg.org/qi9j4yf1j/image.jpg). All components are still stock. Any easy well to tell without disassembling?
    – seanrco
    Sep 13, 2015 at 1:17

2 Answers 2

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Your bike has a conventional threaded bottom bracket (square taper). Since its a relatively new bike, it shipped with a sealed (*) bottom bracket. So, the only maintenance that can be done is tightening the bottom bracket cups (which hold the bottom bracket in place) and replacing the bottom bracket itself (which is a sealed unit containing the bearings, axle, etc.

So, the lube you're squirting is just helping your head. You may have a loose bottom bracket cup which you can tighten by removing the crank arms and then using a bottom bracket tool to tighten them up. But otherwise, the only other maintenance that can be done is replacing the bottom bracket.

That being said, bicycles are notorious for having creaking seem to come from one area but its really coming from another (since bicycles are hollow tubes, they transmit sound in weird ways). My guess (unencumbered by the thought process) is if the creaking is coming from near the bottom bracket area, I'd start by looking at the crankset (chainring bolts, crank arms, pedals) and then the saddle/seatpost. There are lots of good pages on diagnosing creaks (and this). And some bottom brackets just creak even if they're working fine.

(*) Sealed bearings don't mean that they're operating completely sealed away from the environment -- details are given in this article by John Allen. But this point doesn't really matter in this case.

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  • Thanks a lot of the detailed information and explanation. I'm now knowledgeable of the various bottom bracket type which helps explain the various maintenance methods. Thanks again!
    – seanrco
    Sep 14, 2015 at 23:23
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I would avoid doing this. If the Teflon lube has any kind of solvent in it (which it probably does to carry the Teflon), it will break down the grease in the bottom bracket. Eventually, the grease will thin out enough that it will flow out of the bottom bracket, and No More Lube=A Very Bad Thing.

If you are using a basic cartridge bottom bracket, they are typically not serviceable, and you'll have to replace it when it wears out. Higher end cartridge BBs have replaceable bearings.

If you have a more traditional-style cup/cone/spindle BB, you can service it, but you'll have to remove everything. After cleaning and checking for damage, reassemble with a heavier lube (marine grade bearing grease is good; available at most auto supply and hardware stores) to resist the wet, and go ride!

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  • The solvent in most Teflon sprays is very volatile and will evaporate rather than build up. So unless you put enough in there in one go you're unlikely to wash the grease out. It's not going to help either though.
    – Chris H
    Sep 13, 2015 at 13:22
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    Thanks for the comment! Although I gave the answer to Batman wanted to give you a plus one for your great response. Both comments were insightful for me.
    – seanrco
    Sep 14, 2015 at 23:24

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