Bicycle lights- Indicating in the dark I am a product designer and am currently working on a bicycle lighting project and would really appreciate your valuable feedback. 

In England, turning left on a bicycle is not really a problem as you would just follow the road, but turning right can be an issue as often you would have to change lanes or cut across traffic. Likewise in other parts of the world where you drive on the right, turning left would be the issue. That is why it is so important to use hand signals, so motorists can see your intentions. But how can motorists see your hand signals in the dark?

I have an idea for a bicycle light which would clip onto the sleeve of your clothing; very much like the way an ipod shuffle would clip onto clothes. It would always be on; therefore acting as a safety light as well. If you wanted to turn right, you could put your arm out and then motorists could see your intentions through the flashing light. 

Many people have tried to crack the cycling indication market before, but it involves adding expensive and ugly lights to your bike. What if there was something as easy as the above, that just clips onto your sleeve- no need for bike modifications and probably less than a £10 spend.

This in mind, any answers to the following questions would be great:

Do you find it difficult to indicate in the dark? Do you think an idea like this would improve bicycle safety? Would this be something that you would buy?
It's not clear from your question whether you ride regularly a bike, but really the best way to understand the requirements for a product like this is to get on a bike and do a bunch of riding around at night.

When you do this you'll find that the visibility of signalling at night is not as big a problem as all that. First, the proper approach to making a manoeuvre is look–signal–look–move: that is, you always check that it's safe to move and never presume that anyone has seen your signal. Second, bicycle position within the carriageway is a clear signal to other road users of your intentions: if you are positioned towards the left side of the carriageway, you intend to go straight on or left, and if you are positioned towards the right side of the carriageway then you intend to turn right. (Assuming drive-on-the-left as in the UK.)

Nonetheless, there might well be people who would like to buy lights to improve the visibility of their signals, so I'll make a couple more comments:


A device that clips on to clothing depends on you wearing long sleeves and so will not be usable in the summer.
If you're going to wear a light on your wrist for signalling then the light ought to be visible from all directions (so that it does not matter which way you put it on or how you hold your arm while signalling). The best shape would be a bracelet with lights all around.


So if I needed a device like this, I'd buy a SlapLit LED bracelet.