FROM THE WORKSHOP...

If they’re worn out or you need more gears, you can easily swap your chainrings for new ones

FORWARD LOOKING

With the crankset off (see last month) you will need an Allen key of the correct size to fit the bolt on the front of your outside chainring, but don’t turn it yet.

DESK TIDY

Keep everything together and tidy so that when it comes time to put it all back again you will know exactly where the parts are. Give the bits you will be keeping a wipe and lube.

INSIDE JOB

The inner ring will have a small tab on the inside of the outer part of the ring, which also needs to be fitted behind the crank. The ramped edge of the teeth – which aids shifting – should be visible.

REAR VIEW

You will also need another Allen key, often 1mm larger, to hold the chainring nut in place on the rear of the small ring. Secure the nut and unscrew the bolts anti-clockwise.

RING THE CHANGES

When replacing chainrings, pay attention to their rotational alignment. The outer ring has a small pin sticking out to be installed so it’s behind the crank arm, where it can help avoid a total chain jam.

TOGETHER AGAIN

With rings aligned, place each nut into its bolt hole. Secure the nut, then thread each bolt into its nut clockwise until the rings are held in place. Then move from bolt to bolt, a quarter turn each time, until tight.