The Helmet Light
When you’re planning to ride at night your are going to want two lights pointing forward. One on your handlebars, the other on your helmet. It’s generally better to have the brighter light on your helmet but since it’s brighter it generally requires a larger battery which is not ideal on your head although some models allow you to place the battery in your jersey pocket. Even if you do get a smaller (dimmer) light however, you are going to want to make sure it’s still marginally bright, about 200 lumens. Anything less than that you’re going to have a hard time seeing wherever your handlebar light isn’t pointed, say when going around corners and your handlebars aren’t yet turned. In addition, being able to point your light directly at motorists to get their attention will help to make sure that they see you.
The Handlebar Light
If you opted for the dimmer helmet light to save weight on your head, you’re going to want to get a brighter handlebar light. You can mount the battery pack on various parts of the bike if it’s not condensed enough to be one unit within the light. Some handlebar lights can get super bright, like a car on high beams bright, which is great on technical trails or bumpy roads. The best thing with these lights is that they have the capability to be that bright if needed but even at half power are pretty freaking bright allowing your battery to last longer than your legs can.
The Bike Taillight
If cycling at night on roads, you are going to want a bright tail light. One that even grabs the attention of the drunk driver on their phone. One such as this. The biggest thing with taillights is to make sure that they are positioned so that they can be seen by a driver behind you. This means that if you have a saddle bag and you place the taillight on your seat post, the driver may not be able to readily see it. In addition, if it’s a pretty directional taillight, meaning it’s super bright in one direction but not so much to the sides, you don’t want to place it on your seat stays where it points up into the air at a 45 degree angle. You want it positioned so it points directly at the drivers behind you.