Well, they will now, thanks to an innovative jacket with flashing indicators on the sleeves and brake lights in the back.
Its inventor Michael Chen has landed a design award for the high-tech coat and hopes to find a manufacturer to produce it on a mass scale.
Amber indicators are triggered to flash by a "tilt-switch" when the wearer raises their arm to give a hand signal.
And a device called an "accelerometer" is used to turn an LED, woven into the jacket's back, green when the rider is moving forward or red when they apply the brakes.
London-based Mr Chen, 28, got the idea watching cyclists in the capital. He said: "There is a lot of hostility from bus and cab drivers towards cyclists.
"Cyclists are brave. It is so dangerous without bike lanes. When I visited Korea last year, I noticed their cities had better bike lanes than London."
Scroll to the bottom of the page to see the jacket being road tested...
According to the latest official statistics, 148 cyclists were killed on roads in the UK in 2005 - up ten per cent on the previous year - and thousands more were injured.
The Parliamentary Advisory Council for Transport Safety blamed the increase on more inexperienced cyclists taking to the roads.
Now Mr Chen, who studied design engineering at Middlesex University, hopes his jacket will make cycling safer.
He said: "My prototype had lights taped to it that everyone thought was pretty ugly. But when I put the wiring inside, it looked more normal.
"Riding around London, people wave and chase me down the street, asking, 'Where did you buy that jacket?'"
The invention has already impressed British judges of the prestigious James Dyson design awards, who chose Mr Chen for a first prize of £2,000. His jacket will now go through to the global stage of the competition.
Mr Chen hopes the jacket be on sale by Christmas, for about £100.