Off camber corners

[BikeSpeedman]

I've made a lot of progress at different parts of Thunderhill East. I've gotten my corner speed up in 1, 2, 5b, 8, 14, 15.

I am wanting to start getting my speed up in 3 but it's off camber and I am not sure I know how to attack it safely. I've heard approach off camber like a decreasing radius but I'm not sure what that means. I'd rather ask  now than after a crash and then get those "Oh, you have to ______ in off camber corners."

I realize the basic premise of having less grip but I also know I'm not on the limit. I'm looking for specific techniques that you have to use on this kind of corner.

Thanks.

[Jaybird180]

There is a Reference in TOTWII that covers the effect of camber on a corner. Don’t have mine in front of me to give you the chapter. But it covers its effect on lean angle.

[Dylan Code]

Generally speaking you would want to apex it where it is the most off-camber.

[faffi]

I would expect it to be more than just the angle between the road surface and machine/man that comes into play since you are now also facing gravity in a negative manner; it's like standing on a slope. Hence you cannot just use your knee as a guide to how far you can safely lean. Perhaps it's a case of going faster until you crash and then back off a little 😄 Personally, I treat them as I would a surface with less grip, but I only ride on the road. On a track, if you want to find the limit, I would suggest being smooth and add a little bit of speed while feeling for the tyres starting to slide. It may also be wise to square the corner off a little more than typical in order to keep apex speed lower and also the period of maximum lean shorter.

All that said, you really should not listen to me because I do not actually have a clue 😔 

[Spaghetti]

The lower grip on off-cambers is due to the bent on the track increasing the outside force (gravity) and putting slightly more pressure on the side wall. If there wasn't any difference in forces, then the bike and rider would just be on a different plane and the knee would still work as a lean angle reference point. Imaging pivoting the image of the bike+rider at lean from a flat surface to an off-camber one. The profile is exactly the same, you're just tilting the surface line.

There is one small grip advantage though: when riding towards an off-camber apex the bike is going slightly uphill ("climbing" towards the apex). It's not always the case, depends how the turn is designed. This is more obvious on a sharp off-camber turn. The uphill ride loads the rear and reduces braking distance, so changing the racing line to maximize the uphill ride can improve bike stability.