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My mountain bike has a BB30 bottom bracket that was clicking under power. The bike is only a month old, so I figured, break in period, and I took the crank off and greased everything up with teflon grease. I coated everything I could get my hands on in the grease, and re-tightened the crank to the specified torque ( 430 inch pounds ).

Much to my frustration, the clicking is back when under power, after riding a mile or two. What is my next plan of attack?

Updates: I tested a different pair of pedals to rule out the pedal bearings ( no, I didn't swap left for right ). I tried tightening the chainring bolts several days ago, no changes there. The crankset is some sort of SRAM Truative triple. Unlike the cranksets I've owned in the past, there's a ring on the non-drive side with an arrow on it, I'm wondering if it's a suspect at this point. crankset non-drive-side

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  • First: your BB has sealed bearings, so greasing it is pointless. Second: don't assume that it's the BB that's clicking. When you lean on the pedals, you're putting torque on almost every part of the bike. Any one of those parts could be making noise.
    – Mike Baranczak
    Commented Jun 10, 2014 at 3:43
  • If its a month old bike, you should be able to just take it back to the shop you bought it from and they should be happy to fix it for you for free.
    – Batman
    Commented Jun 10, 2014 at 4:35
  • The shop is backed up for 4 weeks.
    – Scott Hillson
    Commented Jun 10, 2014 at 5:01
  • If the shop is backed up, you could always buy yourself a replacement and fit it yourself. I know this goes against the grain - you have every right that the bike you just bought should work perfectly - but if you just want to get out on the bike it might be easier just to bite the bullet
    – PeteH
    Commented Jun 10, 2014 at 7:27
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    Generally one of four things: A pedal bearing is bad, the chainring bolts are loose, a crank arm is loose, or the cartridge is shifting in the bottom bracket. The loose crank arm is the worst, since it will destroy the crank arm and, eventually, the crank shaft.
    – Daniel R Hicks
    Commented Jun 10, 2014 at 10:17

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The NDS bottom bracket cup isn't installed correctly in your photo; you have a 2-3mm gap between it and the frame when there should be no gap at all. If that's as far as it gets with the spec torque (40Nm usually) then remove it and check the threads on both the shell and cup for anything which would stop it going in all the way and clean anything you find off.

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