It's not difficult, much the same as any other bike.

There are many ways to skin a cat, but the way I tend to do it is something like this:

1. First remove the front sprocket cover and bend back the tab washer (do not remove the chain).
2. Run the bike up to a wall (or immovable object) so the front wheel is jammed against it and stick it on the side stand and make sure it�s in neutral.
3. Get a mate to stand on the back brake.
4. Loosen the nut with a decent length extension bar.
5. Loosen the rear axle nut.
6. Then put the bike up on its centre stand/paddock stand/WHY.
7. Loosen the axle nut some more, slacken the chain adjusters off fully and push the wheel forward, which should give you enough slack to unhook the chain. (If not you'll have to take the axle out.)
8. Remove the front sprocket tab washer, nut and sprocket.
9. Swap for the new sprocket (making sure it�s the right way round).
10. Refit tab washer (which have two tabs, one of which may not have been used before) and nut and initially tighten.
11. Refit chain, adjust and tighten axle nut.
12. Get the bike back up against the wall on the side stand as before with the back brake held on.
13. Torque front sprocket nut to 120 Nm and then bend over tab washer.
14. Torque rear axle nut to 105 Nm.
15. Refit sprocket cover.
16. Re-check chain slack and adjust if necessary.

A note of caution: It�s not advisable to attempt to crack the front sprocket nut with the bike in gear as you could run the risk of breaking something inside the gearbox (especially if using a rattle gun!)

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