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Bottom bracket repair


BigJosh's picture

By BigJosh - Posted on 27 April 2011

I was riding at Stromlo and I noticed a squeaking sound coming from the bottom bracket. I want to repair/replace any parts myself. Do I need any special tools to do this job, and if so, what tools? (I don't want to take it to a bike shop because the last time I went, they forgot to put the axle back in the wheel :/)

Brian's picture

What bike and what type of bottom bracket.

Rob's picture

Oh dear - don't think we want to know Eye-wink

If you bike is pretty mainstream I would imagine you probably have a BB with external cups, do they look like this?

BB

In which case you need the tool that unscrews these.

Can you tell us exactly what type of cranks/BB you have?

BigJosh's picture

Well the crank arms say Hussefelt Howitzer so I'm assuming the bb will be the same? The bike in question is a Norco Sasquatch 2007.

BigJosh's picture

Yes Rob, they do look exactly like this Smiling

browny's picture

Before getting too convinced it's the bottom bracket take your chain off and confirm the BB is where the noise is coming from.

It can be tough to locate the exact issue sometimes as the noise can be transmitted through the frame which masks the true source.

eg I swore that I had killed my BB bearings on a long wet ride one day but at home with the chain off everything was running free and silent. Turned out I had cracked a jockey wheel and under it was opening up to allow water and a little gunk into the bearing which caused all kinds of nasty noises.

Fatboy's picture

I agree with @browny. Often the noises come from elsewhere. Also check your chain ring bolts and crank arm bolts as a loose bolt there often makes a squeek as you pedal.

philberesford's picture

They get me every time! So check 'em

spudatm's picture

Grab both crank arms and try and muscle them up and down. If there is play this is usually an indication that the BB is gone. The other one that tricked me was that my pedal bearings had gone and that was causing a creaking noise. Could have sworn it was the BB but I was wrong.

pat.o's picture

Before getting too carried away with the bottom bracket, it's worth ruling out other sources. Unless you can get the bb to squeak when you're not standing on the pedals it can be hard to isolate where the noise is coming from.

A while ago I had a squeak for weeks/months that a home bb service didn't fix. Good news story from the LBS, though (Cranks at Nth Sydney), they offered to have a look straight away (took half an hour) & it ended up being the rear der. hanger that needed a bit of grease.

I noticed that they'd also greased the cable guides too, so that could be another possible source. Other squeaks I've had before were pedals and the seat post. Also occasionally get noise from the front of the seat where the rails slot in - the LBS suggested I leave some light grease or oil in the saddle overnight with the nose down & I had to do it a couple of times before it worked for good (although you're unlikely to confuse this with the bb it drove me mad for months before I got that simple advice).

Torpedo 7 have the union bike tool set on for $40 again at the moment - it's not a professional set but more than adequate for my home service needs - http://www.torpedo7.com.au/products/UNTOON9TB/ti.... Hard to go past at that price.

BigJosh's picture

Thanks to everyone for replying. I tried the advice on the crank arms and there was no give. I have also noticed a creaking noise while riding and have isolated it to the pedal bearings. As for the squeking I'm not really sure where it is coming from. I took the chain off and the squeaking sound was gone same when i put it back on. However when i actually ride the bike and put pressure on the bottom bracket i hear the squeaking sound.

browny's picture

Noises under heavy load can be tough to diagnose because it can be impossible to replicate when stationary or in a stand.

I've been trying to figure out why my roadie clicks for a few months now.

Turning up my ipod is all I've come up with thus far.

Brian's picture

I just had a loud cracking noise and ended up being the crank shaft needed a bit of grease. It was a loud crack noise only when the left pedal was in the 6 o'clock position. It didn't happen all the time but only while pushing hard. I ended up diagnosing it by using my foot and nearly standing on the right pedal with it in the 6 o'clock position, then I put the left pedal down at the 6'oclock position and just the slightest pressure produced a loud crack noise. I removed the crank from the BB (both bearings felt fine, cleaned and applied a little bit of grease to the crank shaft, assembled and all was good. I did the diagnosis with no chain on as well.

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