Ask many people how much you can carry on a bike and they'll say "very little" — which is nonsense, of course.
You should, however, avoid looping carrier bags on to your handlebars. Not only can they become tangled in the spokes of the front wheel, they can also lead to you losing your balance, which is especially dangerous in traffic.
Cycle luggage is usually fitted on to a rack because proper support allows you to carry more without compromising bike handling. This applies whether you use a wicker front basket, handlebar bag or pannier bags. Good makes of pannier bags include Ortlieb, Vaude, Agu, Carradice and Basil; new wicker baskets can be bought from David Hembrow, who runs Dutch Bike Bits.
If you regularly do grocery shopping, you may like to invest in a trailer. Depending on the make, these fold up small when not in use. One of the best is the British-built Carry Freedom Y-frame Cargo trailers may seem expensive but they will last for years and will earn their keep. See this review of four trailers The trailer pictured above was made in 1950 and is still used weekly for the "Asda run", as well as for carrying items in the garden.
A pet such as a small dog can be carried in a large wicker basket. Larger dogs can be carried in child trailers, which can either be bought new or second-hand.
If you are considering bikes for a commercial enterprise, visit http://www.workcycles.com for ideas.
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