Braking
Hard braking is a skill that takes a long time to master and constant practice. Whenever I instruct on track I always break it down into three parts.
1. Braking Zone; where you are applying the brakes for maximum stopping power.
2. Initial Application; getting smoothly and quickly to maximum braking.
3. Trail Braking; brake release into the corner.
Before you work on initial application and trail braking, it's important to be comfortable with braking as hard as you can. This is best practiced on track at a corner where there is a lot of tarmac run-off.
Maximum braking is not a matter of pulling in the brake as hard as you can. You need to be aware of the limitations such as wheels locking; loss of traction and rear wheel lift. The BMW's electronics will help you but you want to try and always have both wheels on the ground. You'll know when you are reaching the limit as the back wheel will either hop or weave. The front end is all about feel. A key indicator that the front is close to locking is it will start to feel that it is squirming. Bumps in the track surface will also affect braking and you will have to modulate brake pressure over rougher parts of the circuit.
Hard braking is something you will need to work up to in relatively small increments. Pick a reference point, gradually applying the brakes as you normally would. When you get to what you think is your maximum braking, apply a bit more lever pressure. Pay attention to what the tyres are doing and ease off slightly if there is a problem. If your able to brake harder and find yourself with room to spare at the corner you should begin your braking at a later point the next time.
Once comfortable you can then work on initial application. Most tracks have number boards or a familiar reference point leading up to each corner. A lot of where you begin braking depends on the corner prior, and how good your previous corner exit was which will affect your speed. Many riders cheat themselves at the braking marker letting off the throttle slowly and putting their fingers on the brake well beforehand... and then grabbing the lever at the reference point. You want to transition between the throttle and getting you fingers on the lever as quickly as possible. Do not just grab the lever, but apply the brakes progressively and harder. It will also reduce the risk of locking the front wheel... and crashing. After the initial application you want to get to maximum braking as quickly as possible.
At the far end of the braking zone, the entry to the corner, you will have to gradually release the brakes as you lean the bike into the corner. Most people simply don't realise how late - and how much - you can brake with the bike at lean, arcing into a corner. It also makes it easier to steer as the front suspension is compressed changing the geometry. In many chicanes, when you are on the brakes right into the first part of the corner, you can just flip the bike onto its side. Anywhere you are off the throttle and on the brakes you will have the front end loaded and it makes changing direction easier.
Trail braking is a skill. When you can do it, and understand and feel what the front tyre is doing, lap times will fall. Finding that feeling is the hardest part, and something that you have to steadily and carefully work up to. Realistically, as the bike is tipping in, you should be getting lighter on the lever and it should be released by the apex. It is not something to work on simply by braking later and hoping for the best when you get into the corner and have to turn in on the brakes. Rather, brake at the same point, but keep the brakes on a bit longer, as you tip the bike in. Once you get the feel for what's happening and are comfortable with a certain level of trail braking, then you can move your braking marker closer to the corner. Keep working in steps, adding more braking with increased lean angle in increments.
Practice makes perfect on track but always be progressive with your braking. That and use the instructors who are normally always free to help you.