Banked turns, called berms, are a common feature of bike parks and local trail networks. Berms give your tires great support and traction so you can hit them faster than flat corners, and if you enter a berm just right, you can leave with even more speed than you had going in.
Beyond your basic cornering technique, like braking before the turn, looking ahead through the exit, and maintaining good body position, you need to think about two things when you hit a berm: line choice and lean.
Video: Riding Bermed Turns
Choosing Your Line
Generally you want to start high and end low, just like a flat turn. You want to enter wide and exit tight. When you enter high, your turn happens early and you can use the downward slope to help you gain speed out of the turn. Just be careful not to enter too high and fly over the top.
Sometimes the high line isn't an option so you have to enter lower and make your turn later. Be careful any time you enter low because the berm will push you up high and threaten to send you over the top. Also keep an eye on the trail conditions because the gravel and loose dirt tend to collect at the low point.
It's super important to look ahead so you know which line you have to take, especially if you have to enter the berm low. Make absolutely sure to do all your braking before you hit the berm. If you have to brake mid-turn, you're way more likely to lose control.
Leaning
How much you lean the bike over depends on how steep the berm is and how fast you hit it. Thanks to all the extra support a steep berm gives you, if you're going nice and fast you can actually lean over with your bike. If the berm isn't as steep or you didn't hit it as fast, you'll have to lean the bike into the turn and counterbalance with your body.
No matter which line you take or how you lean the bike, good body position can really help you stay in control through the berm. Keep a slight bend in your elbows to pressure the front wheel. With any corner, look ahead through the exit as early as you can to be ready for what's next.