Braking during cornering

Danvitt

.060 Over
Joined
Nov 14, 2017
Messages
108
Location
Richmond, Indiana
Ride
2013 Roadster
Ran out of rocket youtube videos to watch and now I'm watching all the wrecks and safety advice. I thought this might be interesting to some as this video teaches counter to what I've been taught.

I've had it pounded into my head to brake before you enter a turn while the bike is still upright, then roll on the throttle a bit as your leaning and going through. I was taught that touching the brakes while leaned over is a sure fire way end up on the ground. Apparently this is not the way to do it.

This video says to lightly touch the brake (no grabbing, just enough to light up the brake light) and this will shift the weight and preload the tire a bit increasing the traction footprint. However, you do need to have a practiced and gentle hand before attempting it. A lot of what they say makes sense to me. Even those these guys are a bit comical and act like their in an infomercial (plus I think the guy on the right sounds like joe dirt). Might be worth a look.


 
@Danvitt
Although merely a teaser regarding the subject, this is very excellent video introducing the trail-braking concept.
I would humbly add for those interested that you REMEMBER that they are speaking of ONLY a 1 out of 10 scale of brake application entering and exiting curves.
I really like what they teach about the importance of gradual and never abrupt brake or throttle application.
Your peak stopping friction is developed before the tire begins to skid, so that is the sweet spot for peak braking.

I would add that the friction circle is still in play. Newton's laws apply to motors, the same as to cages. With a motorcycle the more lean angle, the more friction that is required to hold the roadway in a given radius.
The tangent of the lean angle = the minimum necessary friction value to maintain traction. Most dry, level paved public roadways yield about .75g friction or about a 37° lean angle. Adding brakes while in a turn exponentially reduces the available friction.

friction circle & Pythagorean theorem
upload_2017-12-4_0-6-23.png

Example:
Your race track surface can yield a friction value of 1.0g - if you lean at 45°, you will require at least 1.0g just to maintain traction and not slide out. Nothing is left for ANY braking!
As depicted above, a lean angle of 20° requires at least .36g. This leaves you just a .64g maximum margin for braking.
 
If you can't stop the bike in the distance you see then you are going too fast. Therefore you should not be going through a corner so fast that you can't use the brakes. On a race track, where you have a nice little man from the village letting you know if there is a problem ahead, it is different.
 
What I have been trying is to enter turns with the Rear brake ON at various degrees. "Trail Braking" It depend of the type of turn. This way I can keep some throttle ON through the turn rather than throttle up from idle.

Now, checking the front brake while leaning :unsure:? My fingers are not long enough. Perhaps I need different levers.

On the Sportster, I entered a turn with the front brake on, hit dirt and skid @ mid corner. Its so sudden it is hard to adjust for that. :eek:
 
On a race track, where you have a nice little man from the village letting you know if there is a problem ahead, it is different.
Or maybe not - I've just sat and watched this again. After a while I go MEGO (My Eyes Glaze Over) - I ride fastish - but geez.
 
I have rarely braked in a turn and only as a last resort when I find myself in a bit of a pickle, such as a decreasing radius blind turn or in a steep downhill turn. I always used both brakes, being mindful that doing so would cause the bike to lift a bit. My son took a course on riding in the Alps while stationed in northern Italy and learned to gently use the rear brake if accelerating in a steep downhill turn, common in the Alps.

I tried it while riding in the mountains and found I could safely slow myself. Good video
 
Or maybe not - I've just sat and watched this again. After a while I go MEGO (My Eyes Glaze Over) - I ride fastish - but geez.
Having been there twice , even the video don't do the speed justice . You should try taking a photograph of them roadside? I had half a film of either empty road or a blur of back tyre !
 
Learning the performance envelope of one's chosen motor is paramount, but even more so with the heft and rear wheel power that our beasts bring to the table.

Good onya' for recognizing the importance of that and proactively doing something about it, Captain Danvitt!!!:thumbsup:
 
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