This is 250 lumens! More than enough for a bicycle. On a sidenote, One note is that bicycle lights are mounted high, so anything brighter and you are going to blind other motorists in front. Those 1000 lumens stuff that you see on eBay or Amazon are meant for off-road cycling
Looks decent enough for my short commute on lit roads, mainly just need one to be seen, not to see with. Reviews say the stated lumen output appears to be highly optimistic!
good price but low lumens would pay more and get something a bit more powerful.