Ron Eaglin again lends us some insight straight from his blog at eaglinar.blogspot.com. This is the first of a three part series about racing at night so take what you need from one of the most experienced racers around.
Here are some tips about biking at night.
Unlike the paddle section where you want to keep the lights off - biking at night is all about lights. I use a mounting system I devised that uses my hand lights (this is in a previous blog - search bike lights). The reason is simply staying safe on bumpy and tricky terrain as you ride in the dark. I use 2 handlebar mounted lights and one helmet mounted. This works pretty well. I also have a small 4th light I use for map reading.
Night navigation at night is all about keeping a very close idea of where you are. Trails that would look obvious in the daylight are sometimes nearly invisible at night. You need to keep a very good idea of your bearing and also make sure you know the distance you have traversed on EVERY trail you ride. My navigation is all about - take this trail for 1.2 km to an intersection, take trail at 140 degrees - staying on trail for 2.3 km to intersction, etc... I take measurements and write them on the map for the entire course before the start of the race. If I need to make changes on the fly - I use km since the map grid on a USGS map is in km, and it is easier to judge distances. Odds are most trails you will use will be rideable (or at least obvious).
I make sure at least one of my team-mates is double checking my distance. I also want a second bearing from team-mates. This keeps them occupied. The most dangerous thing is to have a strong biker on your team pushing you to go faster and then you end up way off track. Slower is most often better at night, since a mistake can cost you miles and lots of time. Make sure of where you are - and be careful of following other teams make the mistake (going to lights) that I mentioned in my trek nav blog.
I've taken some pretty good falls biking in races at night. Many more than during daylight racing. For some reason following narrow single track or riding vehicle ruts is much more difficult in the dark. I find that trying to stay relaxed (which is natural in the day) is much more challenging at night. The same techniques that are good practice in daylight are the same at night. Of course good lights are still important. If one team-mate has good lights let them lead and work as a team. Lastly - keep much closer track of your team-mates. I've had them disappear during day races (especially long ones where it is challenging to keep track of them as you get tired). At night - it is very easy to get ahead or behind, especially if they have to drop off. If you have a team-mate that is hurting or weak - keep them in the middle of your line.