Bottom Bracket Maintenance

[aerobrain]

Hi

I'm trying to be good and keep on top of cleaning my bike. The one thing I've not yet done is remove the cranks and chain set to clean properly around the bottom bracket.

I've got two questions really. Do I need any special tools (its a shimano Tiagra double with shimano bottom bracket, stock version for a Specialized Allez Elite) and when I get them off what should I do/look for on the bottom bracket?

Cheers

Lee

 

[Flying Dodo]

You should be able to keep the area around the bottom bracket clean without removing the crankset. Unless of course you mean you want to remove the bottom bracket to clean the inside of the frame and the spindle of the crank set, which on some bikes, if they have an access hole underneath, can mean dirt getting in.

You'll need a special tool to get the BB out - about £10 or so. Then once it's out, clean it all up, re-grease the threads and screw it back on. As the bearings are a sealed unit, there's no maintenance needed on it.

 

[smokeysmoo]

Do I need any special tools (its a shimano Tiagra double with shimano bottom bracket, stock version for a Specialized Allez Elite)

You need one of THESE for the pre-load cap

You need an allen wrench (5 or 6mm IIRC)

You also need one of THESE to remove the BB.

When I get them off what should I do/look for on the bottom bracket?

Not a lot as it's a sealed unit. You don't need to remove it unless it's grumbling, in which case just throw in a new one.

If you strip your cranks though just make sure all faces are clean before re-assembly.

 

[aerobrain]

Cheers guys. Is copper grease OK for greasing the threads?

I just want to get to the point I know how to strip it all down and what bits to pay attention to so thanks for the note on sealed bearings.

Will order the tools as they seem quite cheap and want to upgrade the cranks soon anyway.

 

[smokeysmoo]

Cheers guys. Is copper grease OK for greasing the threads?

Yup.

I just want to get to the point I know how to strip it all down and what bits to pay attention to so thanks for the note on sealed bearings.

It's a doddle with the right tools.

THIS video might help you.

When you come to re-assemble things just remember, when you've slid the non-drive crankarm onto the splines, you then use the pre-load cap to seat it correctly. The tool I linked to, (THIS one), is designed for hand use only to prevent over tightening, (which would cause premature bearing failure). You can use a 20p, but for £1.79 it's worth getting the tool for the job IMO.

 

[Somewhere]

http://www.wiggle.co.uk/lezyne-external-bottom-bracket-and-cassette-tool/ is good type too as it comes with a cassette tool as well. It's particularly good if you end up with a full suss mtb where the normal type tool may not fit due to swing arm. Still need the plastic bit though.