Without question, a high quality rain jacket is going to be the most important item of clothing for wet weather riding and racing. Technology has come along in leaps and bounds in the last decade or so, so take advantage of the latest offerings. We recommend a jacket that is waterproof, breathes well, and fits quite snugly; a flappy jacket will slow you down and likely be hard to roll up small. Keeping your core dry, or at least warm, is the key to a good day on the bike.
Shoe covers, or booties, are another very helpful item in your wet weather kit bag. Well insulated and waterproof booties are ideal, and it's an added bonus if they cover the height of your socks. Likewise with gloves. Good gloves to look for will be waterproof, breathable, and nicely insulated for those colder rides. Pro tip: pull the rain jacket sleeves out over the top of your gloves so no water runs down inside your gloves. If you're planning a longer day in the rain, take spare gloves and shoe covers in a plastic bag in your pocket. Changing these items at the halfway point can be great motivation for that final push to the finish.
Tyre pressure has been a hot topic in recent years. Trends have moved away from very narrow and high pressure tyres, to wider, lower pressure for more comfort and less rolling resistance. In the wet, we recommend reducing your tyre pressure by 15psi (1 bar). This will mean you have more rubber on the road, and more grip than if you run at the tyre manufacturer's recommended pressure. If the terrain and road surface is rough and technical, you might get even more benefit from taking out a further 5-10psi. Lower tyre pressure will make your bike feel slow and heavy for the first 20-30 minutes, but after that it will feel faster.
A cap is extremely useful under your helmet in the rain. A lot of the water, particularly road spray, will be coming straight at your face. Wear your cap down quite low so it just covers the top of your sunglasses, so you keep as much spray out of your vision as possible. Pro tip: wash your sunglass lenses with dish soap and leave a tiny bit of soap on the lens; this will help repel water and stop it sticking to your sunglasses lenses.
Ditch the leg warmers. Wet leg warmers can be quite heavy. This extra weight will make it harder to pedal. A great trick is to put oil or Vaseline on your legs to repel water. If it's cold, put some sort of embrocation cream/oil on your legs before you apply the oil/Vaseline. There are some great purpose made products that include both embrocating and water repelling properties. Test these before using in your event, as sometimes they can be too hot! Pro tip: clean your hands thoroughly after applying oil and embrocation, the last thing you want to do is touch somewhere sensitive with embrocation on your hands!
This isn't the most common trick, but in the cold it can be helpful to add some Vick's Vapo-rub to your chest and under your nose. Don't ask why, but it seems to help!
Another cool trick to repel water off your outer garments (rain jacket, booties and gloves) is to treat them with Scotch Guard. A night or two prior to your event, coat your garments with Scotch Guard. Let the first application dry, then spray them again. The Scotch Guard does a great job of repelling the water and spray from your wet weather gear.
Remember to eat and drink! When it's cold and wet, it's easy to forget about eating and drinking. It is just as important to eat and drink in the cold as it is in warmer weather. In fact, with the extra layers on, you will probably be sweating just as much, if not more than on a hot day. Remember to drink often, and carry foods that are easier to unwrap and eat. Pro tip: on cold days, pick soft foods to eat. Some sports energy bars can get really firm in the cold and that makes them really tough to eat, especially when you're pushing hard on the pedals!
As with anything, event day is not the time to experiment with anything new. Test any new things in your lead up training, so you're well aware of how everything works, and how your body will react to it. Riding in the wet isn't fun, but planning and being prepared for the elements will be the difference between a good day and a not so enjoyable one.