Cyclists need to make sure they are well lit as daylight saving ends, say the Cycling Advocates Network.
But those using super-bright LED lights should avoid dazzling other road users.
"Flashing super-bright bike lights can be a distraction, so keep them aimed low," says CAN spokesperson Patrick Morgan.
The end of daylight saving on Sunday 7 April means it's time for cyclists to check their lights and batteries, says Mr Morgan.
"Some may be caught out by earlier evening twilight, so we all need to be extra careful."