They don't generally use much oil or owt like that. Couple of things I'd say:
1.Remove the front sprocket cover from time to time, and try to keep that area fairly clean, Chain gunk collects there. Examine the sprocket retaining plate regularly for signs of wear.
2. Don't run the chain too tight. It shouldn't need frequent adjustment.
3. Check the tightness of the rear sub-frame bolts from time to time.
4. The shear bolts that hold on the mirrors are a good idea, but get a spare screw and carry it in your tool-kit. If the mirror gets caught by a car, it'll almost certainly break off, but usually they're undamaged (apart from a few scratches), and can be re-bolted on if you have the screw.
[Edited 21/5/04]
[Edited on 21-5-2004 by moto748]