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One of the questions that I seem to get fairly frequently is what do I think about trail braking.
First of all, it's important that we understand it - in essense,
when using the trail-braking technique the rider carries front brake into the corner, gradually trailing off the brakes while adding lean angle.
The classic technique is to complete braking before
turn-in. This is an easier technique because it separates traction management into two phases, braking and cornering, allowing the tyre to use all its grip for one task OR the other, reducing the risk of
overloading the tyre.
The big problem with trail braking is that because braking forces are using traction AT THE SAME TIME AS cornering, it's easy to exceed available grip. Your tyres have a
limited amount of grip that can be used for cornering, accelerating or decelerating. If you start to combine these needs you have to add up the total demand. If you are cornering hard, you won't have
much traction left for deceleration and vice versa.
So why do it? Well two reasons.
The first is simply advantage - since you continue braking into the corner, it's possible to brake a
little later, enter bends a little faster, and thus get in front of the rider alongside you, and thus block-pass in the middle of the turn. I think you will have spotted where this is going to be an
advantage - on the track.
But there is a considerable difference between riding on the track and riding on the road. We're not outbraking people on the track or trying to squeeze a fraction of a
second off a point-to-point time. Do a risk-benefit analysis:
* the gain on the road in terms of distance and speed is small compared with mastering the basics of positive straight line braking, getting on the right line and carrying speed out of the corner
* it's more difficult to apply then straight line braking and demands pin-point accuracy through the turn - keeping it simple usually pays dividends
* the bike doesn't steer as quickly with the forks compressed
* the bike can't turn as tight with the brakes on because you can't lean as far
* when you get it wrong, it bites - hard!
On the road, the main problem is the last. Getting trail braking wrong leads you straight into some of the worst situations you can find
yourself in on the road, it's definitely a big risk for a small effect. Misjudge your braking or misjudge a tightening bend, and you're entering the corner too fast:
* you'll be off-line running wide - turning tighter is difficult when braking
* pushing the limit of traction
* suddenly aware of all the cars, walls and other hard objects, leading to target fixation and freezing on the controls
* if you do make it out the other side, you'll be late to get the bike upright and late on the power - everything and more that you gained by late braking, you just lost
On the road, braking
hard and late is rarely the key to riding fast - it just unsettles the bike and unsettles the rider! If you're fighting the bike into the bend on the brakes, you've got your hands full just making the
turn. If you see them at all, any nasty problems will be much more difficult to deal with than if you are smoothly balanced on the controls, because the loading on the tyre severely limits both your
braking and tighter turning options.
In my opinion as well as a number of other expert riders, in dealing with a bend the most important survival skill is getting your corner-entrance speed set
early, or as Kenny Roberts says, "Slow in, fast out." It's worth mastering the art of braking hard in a straight line - you can shed a surprising amount of speed in a surprising short distance
- and with the bike upright, any skid that does occur is rarely much of a problem to correct.
Setting your entrance speed early and looking into the corner allows you to determine what type of
corner you're facing, anticipate hazards and pick your line. On the track, you'll already know exactly where you are going. On the road, even a bend you know intimately will have different hazards every
time your ride it.
On the road, where no-one is going to outbrake you and pull a block pass, the deep entrances, late turns and quick steers of the Point and Squirt technique claw back most of the
advantage of trail braking, as well as giving a better view of the road ahead before you commit yourself. Being off the brakes allows you to get on the throttle early, preferably as you begin to turn in.
The bike settles down and simply works better with the power on. Getting the bike upright sooner allows you to put the power on harder, earlier coming out of the corner. Finally, the tighter line is
safer, with more room for error.
I mentioned two reasons for trail braking. The second reason is you might have to brake mid-turn - that nice easy looking corner tightened up or there's a stray
cow wandering around mid turn. Now we are talking about an option to use a skill that is of genuine use on the road. But if we've already shed most of our speed in a straight line, and are using a
moderate lean angle, now we have grip in hand and time to make decisions, the first of which is "could we avoid the problem by changing line?" Again, it's the simpler, less risky option.
If you decide you have to brake then application must be gentle and progressive - grabbing guarantees you lock the front or stand the bike up. The bike sits up on the brakes so to make the turn you will
have to make a positive countersteering input. When you release the brakes again, do so carefully and slowly to avoid unloading front suspension suddenly - don't forget, because you are steering the bike
into the turn, it will tend to fall into the corner when you release.
One final comment. I've heard another advantage offered for trail braking. "The bike steers better with the forks
compressed". You'll find this on Freddie Spencer's site and it's hard to argue with a rider as talented as Freddie. It may well be that a race bike with race geometry does steer better on the
brakes, but I can honestly say that every road bike I've ridden has, to a greater or a less extent, sat up and headed for the ditch on the brakes. Nick Ienatsch, another US racer and writer for the US
mag Sport Rider, who incidentally is a big fan of trail braking on the track, agrees in his "The Pace" articles about road riding technique that it makes steering more difficult and that it's
out of place on the road.
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