CLASSIC ADVICE NO1:“KEEP YOUR WEIGHT BACK (ON STEEP TRAILS)”
Whenever trails get steep, or there are rollable drops ahead of you, the advice to keep your weight back pops up. This is understandable, and it kind of makes sense. If you look at any capable rider negotiating a drop off on a steep trail there is a moment when they are off the back of their bikes and their arms are at full extension. The problem with thinking about steep trails this way is that the image of the rider being off the back is only a tiny snapshot of a much wider range of motion. They might look like they are hanging off the back at the worst part of the drop, but they are setting up that maximum extension by doing something completely different on the way in.
Riding off the back seems to make sense initially. It’s defensive, and will feel like you are so far away from the danger that it must be safer. The problem with riding this way is that it causes rotation. If your arms are at full extension, and you are already off the back of your bike, as your front wheel falls into anything you will get violently pulled forward. If this happens on a big enough drop, or a steep enough trail, then that sudden forward rotation will be enough to send you over the handlebars.
When it comes to steep trails or rollable drops the correct way of approaching them is to lower your body towards the bike. Doing this on the way in will allow you a much bigger range of motion, and mean that as your front wheel repeatedly drops into holes, you have enough room in your arms to fill that space and keep your bodyweight neutral. There might be moments when you are at full extension, but remember that it’s only a fraction of a second, and that as soon as your rear wheel rolls off the same drop you will be back in a composed, low, ready position with your arms bent, your head over the stem, and your torso close to the bike. Riding this way will mean you feel like your bodyweight is neutral, and you have more time to see and react effectively to the next obstacle; lowering your perceived exertion.
The correct way of riding steep trails and rollable drops is to think about how to neutralise the forward rotation that a more rigid body position exaggerates. The next time someone says “keep your weight back,” think: “Stay low and keep your weight neutral.”