I hate to say this, but if you're wanting to shave your legs to stop chafing when cycling, you'd have to do them on the day of the race if your legs are anything like mine. I think I may have hedgehog in my ancestry as they get all prickly within hours.
The alternative would be to wax them. Not a pleasant experience, but the hair grows in much finer and takes about three weeks. I just don't have the nerve to try it. Maybe another female on here can advise you on waxing your legs.
As for shaving, until Percy gets round to doing the experiment, I don't know what would work best for shaving legs. In my own experience, I miss bits, can't quite reach round the back, hack off most of my knees and lift little curly scrolls of skin from my shins which seem to bleed for about a fortnight. Getting round the contours of the ankle bones is almost impossible. I've tried in the bath, in the shower, dry, oiled, just wet and no soap, enough soap to suffocate in, hot water, cold water (don't even contemplate this one - I beheaded all my goosebumps!), tepid water, moisturiser, steam. You name it, I've tried it. The only things I haven't tried are gravy and custard and that's because my hubby would ask awkward questions.
If I had the courage I'd wax and I think that's a cyclist's best option.