Crank Set
Together the bottom bracket axle and bearings, the crank arms and the chainrings are known as the crank set. There are two types of crank sets - One Piece Cranks or Three Piece (Cotterless) Cranks. One Piece Cranks are relatively easy to maintain as the crank arms and the bottom bracket are a single component. In Three Piece Cranks the crank arms bolt onto the bottom bracket axle without using old fashioned type cotterpins.
This system requires more detailed servicing.
Crank Arm
Dust Cap
Axle Nut | Tapered Axle |
Chainwheel
Inspection and Maintenance
Every month the crank set should be checked to ensure that it is properly adjusted.
For Three Piece Cranks:
-Check that the crank axle nuts are tight.
-Adjust the bottom bracket bearings as necessary.
-Remove the chain and test for crank movement on the axle by attempting to move
the cranks from side to side with your hands. Only very slight movement in the bottom bracket should be noted.
-Rotate the cranks. Adjust and oil if they do not spin freely or a grinding noise is detected.
-Check the chainrings for any broken teeth, and clean off any excess dirt and grease.
Caution:
Always ensure that your |
Standard Bottom Bracket Assembly (Cotterless)
Fixed Cup
Ball Bearing
Three Piece cranks are |
firmly secured before |
Lockring
Axle
|
| riding. Riding with loose |
|
| cranks is potentially |
|
| hazardous to both the |
|
| rider and condition of the |
52 | crank arms. | |
| ||
|
|
|
Adjusting 
Cup
RAOM0507 | Apollo Bicycle Company Pty. Ltd. ABN: 60 001 914 469 | Updated 23/05/07 |