800 lumens is a superb amount of power for most cross country, road, commute and mountain bike applications, and is exactly what you get from this Exposure Joystick Mk10 Front Light 2016 With Mounts.
The original, and still the best, when it comes to cable free helmet lights, the fact that Exposure have upped its output for this year only enhances this status.
Mounting the light on your helmet, with the included helmet mount, makes you extremely visible. It also makes navigating your trails at night a safer activity as you get light exactly where you are looking, rather than just from a fixed point on your handlebars. Additionally, it means you always take this light and mount with you, so there is no chance of them going missing.
Exposure have always set themselves apart with the intelligence of their designs. Smart Port + is a great example of this. The light recognises accessories, without prompting, to allow you to power additional front and rear lights, use the Remote Switch and charge USB devices on the move.
Other technologies are maybe not as glamorous, but improve performance massively. Intelligent Thermal Management regulates the internal temperatures to prevent your light from losing power.
This light also comes with a superb quick release handlebar mount, that is incredibly secure. Other brackets are available for purchase separately to give you a variety of options.