These days it had rained a lot, so I decided to offer some advice to the less experienced bikers when it comes to muddy trails.
In the first part, our discussion regards the bike and the equipment and later on we will offer some tips on technique. The first step is to equip your bike with proper tires. The range is pretty large and we tend to be subjective when it comes to certain producers or models. As a rule, the mud tires have bigger, well spaced knobs, in order to release mud and have higher traction. Also important, is the size of the tire, which should be smaller than that of the tires you usually use. With slimmer tires you will have better chances of pushing through the deep areas of mud. Important to note is the fact that in XCM (Cross Country Marathon) races you don’t need knobby tires as in gravity disciplines. Keep in mind that you need good rolling tires that shouldn’t be too heavy, even if this means making a compromise between laking traction and rolling resistance. Also, it is important to adjust the tire pressure to fit the road conditions. Lower pressure will give you even better traction.
The second aspect is that related to the bike’s transmission system. Because certain elements of the transmission accumulate mud easier, you need to use a less diluted chain oil. For those that use a crankset with a single chainring (example xx1), they need to be extra careful to a possible chain suck, that is the chain remains blocked on the chainring. If the chainrings are really used you need to replace them.
Regarding the pedals, if you use the clipless system, choose a model that offers more grip. When riding clipped, loosen the screws so you can unmount faster.
Technique tips: choosing your path is really important, but this has to do a lot with experience. Avoid the paths that are not covered in grass and don’t use the most ridden line on the trail because there can be more traction where the path is less ridden. For downhills, choose the straighter trails and avoid sudden turns. Adopt a less aggressive biking style and leave your bike find it’s path. You’ll see that your tires will find the right traction. So, it’s better to relax and try to be one with your bike.
In conclusion, don’t hasten your bike and be extra careful when changing gears.
Mud implies difficult rolling. Keep your speed smooth, avoid as many slowdowns and accelerations as possible. When passing over roots or wet rocks try to choose a straight path and to approach them from a 90 degree angle, otherwise you increase the risk of side slips.
I hope that at least some of the advice above will be useful when having to deal with muddy trails.