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Wow, some great advice!

I grew up riding dirt bikes in the Calif desert. I think this is a better way to learn how to ride and then transition to street.

I bet some dirt bike riders will back me up. I have a neighbor who rides a Honda Valkyrie, he also learned how to ride in dirt.
 

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I'm a newbie for street riding. I did a little bit of it on a street legal dirtbike 30 years ago, but as far as regular riding on public roads, that just started happening this summer now that I'm in my mid 50s.

I agree that If somebody frequently falls off their bike during low-speed tight turning or stopping it is probably due to front wheel lock.

M
y experience in the dirt tells me that if I lock the front wheel during any sort of turn or cornering, I'm going down 95% of the time and it will usually happens so fast there's nothing I can do to even try to correct it.


But a spinning or locked-and-sliding back tire will often leave me upright long enough to try to address the problem. ( sometimes successfully, sometimes not, but it's not like you blink and instantly you're pressing your cheek to the gravel and looking at the world sideways.)
 

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CB125T, EX250 commuter, Ninja 250 racebike, CBR250R(MC19), VF500F, CBR600RR, VFR750F
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It's not front-wheel locking that's problem, it's how it's applied. Most beginners panic, grab both-brakes as hard as they can and end up locking both. Proper procedure is to apply both and gradually increase force. Then as rear lifts due to weight-transfer, let up on rear (or leave it locked as trained in beginner crashes).

In vast majority of crashes where auto cuts in front of rider's path, there's LONG skid-mark of rear locked-up tyre leading right into crash! If they had properly used front-brake only, they would've stopped in plenty of time.


Imagine an invisible-hand pushing back on bike to decelerate. This braking-force is applied at tyre's contact patches. Due to C.o.G. of bike+rider system being higher than this force, weight-transfer towards front due to deceleration causes weight-transfer to front and tipping up of bike around front contact-patch.



The higher the deceleration-force (Bf), the higher the weight-transfer. Maximum amount of braking-force is when 100% of weight is on front-tyre. This is when front-tyre has highest friction f=mu. Similar to wings on F1 cars pressing more on tyres to increase traction. If Bf was lower to put rear-wheel back on ground, deceleration would be less.

Reducing braking-force in this case would have him miss turn and go off-road. Note no back brake used at all.


Even 12-yr old girl can do it!


The solution is improved braking-technique through lots of practice.
 

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It's not front-wheel locking that's problem, it's how it's applied. Most beginners panic, grab both-brakes as hard as they can and end up locking both. Proper procedure is to apply both and gradually increase force. Then as rear lifts due to weight-transfer, let up on rear (or leave it locked as trained in beginner crashes).

In vast majority of crashes where auto cuts in front of rider's path, there's LONG skid-mark of rear locked-up tyre leading right into crash! If they had properly used front-brake only, they would've stopped in plenty of time.

Imagine an invisible-hand pushing back on bike to decelerate. This braking-force is applied at tyre's contact patches. Due to C.o.G. of bike+rider system being higher than this force, weight-transfer towards front due to deceleration causes weight-transfer to front and tipping up of bike around front contact-patch.

The higher the deceleration-force (Bf), the higher the weight-transfer. Maximum amount of braking-force is when 100% of weight is on front-tyre. This is when front-tyre has highest friction f=mu. Similar to wings on F1 cars pressing more on tyres to increase traction. If Bf was lower to put rear-wheel back on ground, deceleration would be less.

Reducing braking-force in this case would have him miss turn and go off-road. Note no back brake used at all.

Even 12-yr old girl can do it!

The solution is improved braking-technique through lots of practice.
I think in general what you are saying is true, that in a lot of crashes, HOW the front brake was applied is a huge part of the problem. In the case of the OP's crashes though, because of the low speed and the fact that he is applying the front brake while turning the bars drastically- that is HIS problem. I'm short, only 5"3 so I have to be particularly careful whenever stopping or slow speed manuvering the bike because I only have tippy toes that barely touch the ground. If I place my foot wrong or have the bars turned too much with some front brake on and the bike starts tipping, I'm going down.

I'm always careful to pre locate a flat area to stop and to approach it straight on, as well as keep my eyes up and not looking down and in front of me. I also put one foot down flat and turn my hips into the bike to get more leverage to hold it up.

Now, in terms of emergency stopping and some of the higher speed, straight on emergency braking scenarios you are referring too, there are one or two comments I'd like to make. One, the rear won't necessarily lift up under max braking- there are things that riders do that cause the bike to stoppie like jam the front brake a little harder at the end of braking or allow their body to slide forward into the tank, both can encourage the rear tire to lift up off the ground. By squeezing the tank with both knees and keeping your arms relaxed, and progressively squeezing the lever you can prevent the rear from coming up.

Also, if you do lock either the front or the rear tire what should the proper response be? Most riders panic in these situations. We have a cool training bike at the California Superbike School that we use to train riders to intentionally lock up the front tire to feel what it's like and to learn what to do and how to improve their overall emergency braking distance. Cool convo :)
 
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