Bottom Bracket Issues


After a few months of riding on my bike w/ a shimano bottom bracket i’ve started to get pissed off by the amount of noise and movement that is coming from it.

On the downwards direction of my left pedal there are quite loud clicking noises (I’ve checked my chain, chain ring bolts and even disassembled my entire pedal and re-lubed), there is also a weird spot of movement at the vertical section of the pedal movement, where it kind of loses friction and has a lot of ‘give’ in it in both directions.

Just wondering if anyone could think of anything else this would be caused by before I pop the cranks off and replace the bottom bracket?

I hope you checked more than just the pedal?? Just cause its on the downstroke on one side doesnt mean its the pedal. Check the taper is ok. Check the crank bolt is tight. Check the BB is tight in the frame.

Is the movement fore/aft or side to side? Maybe your crank bolt isnt tight or the taper is stuffed and the whole crank floats on the spindle.

I’ll be checking the tapers tonight (was trying to get around having to actually take them off). The crank bolts are tight and I have a BB tool coming in the mail by the end of the week to check the tightness of the bottom bracket too.

As an aside, does anyone have a left sided metal BB cup for english thread? The one that came with the shimano one is cheap plastic rubbish. or does anyone know where I could track one down?

The movement is to and fro, no L>R movement at all.

The ‘give’ sounds a lot like the cog and lockring are loose. As familyguy said, creaking is usually a loose/unlubed BB.

Okay, well isn’t this sounding like more and more work, haha.

SanEsteban - do you have a lockring tool i could borrow when I pick up that wheel? And also a chainwhip?

Might as well give my drivetrain a complete service then.

Yeah no prob.

You’re gonna have to take off the cranks to use a BB tool anyway, may as well give the whole thing the once over while they’re off.

If its a sealed BB, the plastic cup isnt doing any work. If it aint broke…

Does it only happen on the left pedal stroke? If it was cog/lockring it’d be at all sorts of spots as the maths on the ring/cog combo spaced itself out. $0.02 = I reckon you’ve rounded off the left hand taper.