Tuesday, July 23, 2013

How To - Cornering, Looking Habits (Pictures)

I often address questions about cornering, whether the rider asks me directly or someone pleas for help on the intraweb. One of the most important things in cornering is to look ahead in the turn. If you keep looking directly in front of you then you won't be able to see what's coming up. It's sort of like the first person view in a driving game - you can't look around corners. It's also the reason I prefer to view helmet cam footage versus bar cam footage. With a bar cam you can't tell what the rider is looking at, where their head is pointed.

Every ride I do from the house and every drive home in the car, I have the privilege of taking a very interesting right turn. It's an acute turn, more than 90 degrees, almost a 180. What makes it interesting is that it's apparent that the designers initially pictured it as a T intersection with a severely bent stem on the T.

However, instead of making it a real square T they widened the entry side (from my "going home" direction). This resulted in a multi-radius turn and severely encourages an early turn in. I'm guessing they made it so that any 18-wheelers would be able to clear the turn without destroying the curb or maybe they adjusted the curb after it got destroyed by the first moving truck that came into the complex.  Whatever the reason the extra room on the right side of the turn makes this a weird turn. The first part is a true 90 degree turn, but then the road immediately swerves right in a very wide radius 70 or 80 degree turn.

In the car it's pretty apparent it's quite sharp, and in fact for a while I was going really wide at the exit of the turn. I mean I live here and I try to be very aware as I drive so to screw up the turn... I wasn't happy with myself.

Approaching the right turn.

As you can see it's a pretty sharp right. The road doubles back on itself to create a 180 type turn. It's not so apparent in the picture but it's quite a steep down hill - on the bike, coasting, it's easy to hit 35 mph. In the car I have to brake to keep the speed under 35 and I typically come down the hill at about 30 mph.

Dash cam has limited sight lines.

Here you can see the problem with the dash cam's aim (and, to a certain extent, a bar cam's). Even though you're setting up for a really hard right turn you can't see it in the image.

About 45 degrees into the turn.

Mid-turn there's very little to see. The landscape just slides sideways across the screen as I turn the car hard to the right.

Turn out.
I'm about to get to a speed limit sign but you can't tell from the dash cam.

At the exit of the turn, or the "turn out" point, I'm parallel with the curb and on the right shoulder. Most residents here (there are probably 60-70 families who live down this road) end up virtually kissing the left curb before they move over to the right. It's a bit annoying to someone like me who drives the other way when I leave the house. For most people it's not a big deal but for us we live at the point where most people are just getting back to the right side of the road.

Note the green thing on the right. It's some kind of utility box.
This is after the puddle from the earlier picture.

I included the last picture to show the green utility box. It's a good point of reference.

Now let's take the same turn from the point of view of me, the rider, while noting where I'm looking, where my head is pointing. Okay, granted, my helmet cam (ContourHD 1080p) is of better quality than my dashcam (DroidX phone, 1080p, running Daily Roads), but still you'll see the differences.

Approaching the turn.

So far things look the same. It's a sharp right turn, curbed so a hard border, downhill, coasting at about 30-35 mph. My hands are on the drops, I'm slightly on the brakes, and I've shifted into an appropriate gear for rolling out of the turn.

First look right.

My head turns most of the way but my eyes are actually looking further right. I'm looking through the trees for any movement - cars typically drive 35 mph or faster and if they do I'll end up at the intersection as the same time as them. Since most drivers here drive in the center of the road it's not good for me if I meet a center-of-the-road driver at the intersection.

Look forward again.

I look forward again. I need to get my bearings down - it's not like I'm going to go through the whole turn looking ahead.

In this shot you can sort of imagine the line. Better yet let me use my incredible Photoshop skillz and draw some lines.

Solid line is the late apex.
Dash line is the early apex.

(Solid line is supposed to follow the curb but it's hard drawing those lines with a touchpad so it veers up  a bit, even though it's not supposed to do so.)

Most people tend to do the early apex. It's not just in bike racing, it's in life. Watch someone rushing to beat a light or take a turn in front of oncoming traffic. They veer to the side as if getting to the curb somehow helps gives them help going around the corner.

When people get scared or unsure they turn in early. I do, when I'm scared or unsure, because the panic instinct is very hard to overcome. The key is to not be scared of cornering, to understand cornering lines, and to apply your knowledge when you corner.

(As a side note most fast descenders are also extremely good corner-ers. They descend fast because they know how to take corners. Since both cornering and descending generally don't take fitness it would be poor strategy to ignore the benefits of proper cornering. This is where a less fit rider can make up a lot of ground. It's also where a lot of fit-but-unskilled racers lose tons of ground.)

It took me a few tries to figure this turn out. Since I live here I got to try the corner every time I drive or ride home, and after carelessly ignoring the tricky corner I finally spent a minute of energy thinking about it. It's nothing too tricky (car racers will probably be shaking their heads at me) - it requires an especially late apex with a hard turn The turn out ends up really early - at about the first tree or so, maybe the second tree.

Most people who drive here take the dashed line. It causes them to veer way to the outside, and if I'm riding from the house (i.e. towards them) they have to slam on the brakes and almost come to a stop so they can get to the proper side of the road. It makes for interesting situations when you consider that many people leaving coming out from the right will stop in the middle of the road, about where the second-last dash sits.

Using the correct line I can enter the corner at a higher speed than a "stay-on-the-right-side" early apex--er and still stay on the right side.

Going through the turn.
My bike is pointing towards about the 11 o'clock direction, not straight ahead.

At some point I'll do a clip of this but in the above shot I'm looking towards the turn out point, where the trees are to the right. My head is pointed to the speed limit sign but my eyes are looking further right. My bike is pointing to the left a bit, leaned way over, turning very hard. It's pointing to about the 11 o'clock direction, so a bit to the left of straight up.

Wide radius part of the turn.

I'm at the wide radius part of the turn. My bike is starting to get closer to the curb, I'm still looking forward at or to the right of the trees. My eyes are being pulled forward like there was a string tied to them, a string pulled by someone just disappearing from view up the road.

Now my bike is almost in line with my head.
No puddles because this cam footage is from a different day than the dash cam stuff.

I'm about to even out with the curb - I'll be next to it as the bare patch in the grass ends and the curb straightens out.

With the early apex I'm parallel to the curb before the curve ends. It's safer for me, safer for oncoming traffic. In a group ride this is excellent because I'm staying out of traffic's way. In a race it's even better -  if you have a mishap mid-turn you have a lot of space to work with, but more importantly you can really accentuate the accordion effect (if you're at the front) or save a lot of energy (if you're tailgunning at the back).

Waitaminute. You forgot one thing, you say to me. Where's that green utility box, the one that signaled the turn out point from the dash cam?

Well if you look past the speed limit sign, between it and the first tree truck, you'll see it way down the road. It's about twice the distance as to the speed limit sign.

With the helmet cam it's clear what line I took and where I was looking. With a bar cam (or a dash cam) it would be much harder. I basically take the same line in both the car and the bike. The dash cam is mounted just to the left of center in the car so it's about 3 feet further left than my helmet cam, but it's clear that the dash cam simply cannot illustrate how I took the turn.

Remember that cornering lines are habits. If you got yourself into the normal habit of turning in early you need to break that habit. You shouldn't practice cornering only on the bike. You should practice it whenever you're taking a turn with a wheeled vehicle, whether it's a car, a shopping cart, or a baby stroller. Break that early apex habit and improve your bike racing.

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