Overhaul A Cup And Cone Bottom Bracket

Introduction

There are many steps to overhauling a cup and cone bottom bracket, so make sure you leave plenty of time. Unlike modern, sealed type bottom brackets, cup and cone bottom brackets can be regularly serviced, and If you're careful, will last a very long time.

This is a long guide, so you can choose to either watch the entire video above, or follow it in smaller chunks by clicking on the individual steps below.

Steps to Overhaul A Cup And Cone Bottom Bracket:

Remove A Square Tapered Crank - MadeGood.bikes

1. Remove A Square Tapered Crank

The commonest type of cranks are aluminium, with square holes that fit onto a tapered square section axle. A nut or a bolt pulls the crank onto the taper to jam it on. They usually need a special tool called a crank-puller or crank-extractor to pull them off the axle.

Service A Cup and Cone Bottom Bracket - MadeGood.bikes

2. Service A Cup and Cone Bottom Bracket

Some bottom brackets can be serviced. Others are fit-and-forget, when they wear out the whole unit must be replaced. Some have cartridge bearings that can be replaced. Identify an serviceable bearing by the lock-ring on the left-side cup

Adjust A Cup And Cone Bottom Bracket - MadeGood.bikes

3. Adjust A Cup And Cone Bottom Bracket

Some bottom brackets can be adjusted to tighten or loosen the bearing. Others are fit-and-forget, when they wear out the whole unit must be replaced. Some have cartridge bearings that can be replaced. Identify an adjustable bearing by the lock-ring on the left-side cup

Check The Cranks - MadeGood.bikes

5. Check The Cranks

Modern bikes usually have cranks made of aluminium, they are mounted on an axle made of harder material, usually steel. If there's any play between the cranks and the crank axle the soft aluminium will soon get worn to the point where it's impossible to lock the cranks. If the cranks are loose don't ride the bike.

Check A Bottom Bracket - MadeGood.bikes

6. Check A Bottom Bracket

The bottom bracket or crank-axle is the bearing on which the cranks turn.