Locking front on asphalt, is it hard on sportbike?

[PorradaVFR]

Aggressive, progressive braking is most likely to lead to a stoppie not a skid, but that's still a valuable lesson. When you hear the front tire "howl" and/or feel the back float or come up you know that's just about the limit of your braking.

Now, do the same on polished concrete (like in many underground garages) and that will be reached more quickly. Personally I have skid the front a couple of times - but never for fun...unless you like to pucker a LOT.

 

[kiltwearinfool]

Yeah I don't think you need to be trying to lock the front. If your rear tire is starting to leave the ground you're probably getting pretty close to braking as hard as you would want to with the front. You should be practicing being smooth while at the same time decreasing your stopping distances.

Gotta agree with this one. Bikes aren't like cars where you step over the line and then dial it back a bit.
I've locked the front on many different bikes, and it was almost always a result of panic due to too much speed for the situation. I've had bikes do anything from lay down a nice long darkie and resume rolling when I let off the brake lever, to the front end hopping along the pavement, to feeling the front end go numb(loss of traction). There was only one time when it was "cool" and that was at a skills class where Gary J told me I should have been on my ass.

There really is no reason to learn how to lock up the front. Your effort will be better spent teaching yourself how to consistently brake with as much force as you can while keeping the front end under control. That way when it comes time to panic brake, it will be second nature.

 

[Yakoo752]

To those who asked 'why', +1. This not a useful drill. Max braking has nothing to do with front lock up. Lifting the rear does, however. (we are talking sprot bikes here).

If you must do it:
1 try it on grass or sand. You can do it at 5-10mph and if you crash it won't hurt as much. I've seen instructors ride this for several yards.

maybe it's not so much of an importance to some as others but 1 is highly useful. I rode around daytona a few nights on a borrowed bike. A1A is a nightmare of sand. Can't tell you how many times I locked the front up. My "experience" of front lock ups prevented quite a few incidents from becoming issues.

 

[OldMadBrit]

Had a moment yesterday when a dear jumped out in front of me on Pescadero Road.

Stabbed the front .. heard a quick errp.. eased of before I heard the errp.. because I knew I stabbed it.. going about 60 I would say.. Maybe the electronics did it.. maybe me. for sure. Lets just say.. errp is not that good in that situation.

Too true

I generally find that "errp" is also the sound track to "my arse eating its way through the seat cover"

 

[ScottRNelson]

There really is no reason to learn how to lock up the front.

I've seen stunt riders do it, and it looks pretty cool. I can't remember his name, but there's a local stunt rider who rides a BMW F800 that was at the grand opening of Tri-Valley Moto who was going at least 20 feet with the front locked, then letting it off and skidding the back around into a 180 degree turn. He had the power ON while the front wheel was sliding, so it didn't have nearly as much weight on it. That is one trick that I definitely don't want to learn to do.

 

[tzrider]

maybe it's not so much of an importance to some as others but 1 is highly useful. I rode around daytona a few nights on a borrowed bike. A1A is a nightmare of sand. Can't tell you how many times I locked the front up. My "experience" of front lock ups prevented quite a few incidents from becoming issues.

I've got to agree here. Again, this isn't a recommendation to go do it on your own bike, but the value is in knowing what can bring a locked front about and what it feels like. When it happens in the real world, other things are going on, like whatever made you snatch on the front brake. It's not the time to wonder what that funny vibration is in the front end of why the bars are suddenly turning so easily.

 

[p4i1]

When you hear the front tire "howl" and/or feel the back float or come up you know that's just about the limit of your braking.

That's pretty much what I consistently got during my emergency stop exercise. So I will just continue doing the same thing trying to decrease stopping distance.
I just needed to know that this is the right indication of braking limit if done correctly.

 

[tzrider]

I just needed to know that this is the right indication of braking limit if done correctly.

Once you pick up the rear, there's not a whole lot more available. A thing to know is that the bike will stoppie more easily when you're straight-arming the bars than of you take the majority of the braking force by clamping your knees on the tank and supporting your body with your core. The bike can usually stop harder before the rear tire comes up if you can stay as light as possible on the bars. You can also better feel and respond to a front lockup, if one should occur.

 

[p4i1]

A thing to know is that the bike will stoppie more easily when you're straight-arming the bars than of you take the majority of the braking force by clamping your knees on the tank and supporting your body with your core.

Actually, thanks for this advice! Yes, I think I was putting to much of a force on the bars because quick deceleration was pushing me forward very strongly. Usually I am light on the handlebars, but not during this exercise. That for sure contributed to stoppie. That's what i will pay more attention to.

 

[ALANRIDER7]

Your time would be better spent working on learning how to confidently approach impending lockup and recognizing the signals along the way. A locked wheel doesn't stop you quickly or effectively. A wheel on the ragged edge of impending lockup for conditions is your shortest stopping distance. You also have to prepare for changing traction conditions during the stop. Just because you started applying the brakes on dry, grippy pavement doesn't mean it will stay that way until you stop. Available traction can change during the process.

 

[HeatXfer]

Back during my 1100F days we used to see who could leave the longest front tire skid: stoppies were impossible on bikes in the early 80's.

 

[SFSV650]

Are there any guides out there as to what are good stopping distances to aim for? Obviously this would vary by bike / rider weight / tire make and condition, but even ball park figures?

I'm glad I found this thread; I was practicing progressive braking from 30 - 35mph yesterday and was wondering if not locking the front wheel meant I just wasn't trying hard enough.

 

[sanjuro]

BTW, locking the front brake is like punching yourself in the face.

No matter how hard you try, self-preservation prevents you from doing it.

Doesn't mean when it really counts, it won't happen.

 

[tzrider]

Are there any guides out there as to what are good stopping distances to aim for? Obviously this would vary by bike / rider weight / tire make and condition, but even ball park figures?

From a training program I've been involved in that targets enthusiasts who are typically male and in the 22 to 35 year age range on a variety of sportbikes:

Average stopping distance from 60 mph before training: 183 feet
Average stopping distance from 60 mph after training: 129 feet

 

[R1-Limited]

I was practicing my emergency braking today. Empty straight road, dry, clean pavement, ~30-35 mph speed. Stopping to 0 with both brakes.

So... I was thinking I would try to brake as hard until front locks to try modulating it. But I was not able to lock it . Instead my rear was up in the air just a little bit and locked. Flipping the bike or doing and stoppies were not in my plans today. And pulling front brake more rapidly and harder is too scary.

My question to those who know - how hard to lock the front on DRY, CLEAN ASPHALT without making a stoppie?

What is your purpose or what do you expect to achieve by doing this?

IMO locking the front is a disastrous move or reason to try. Good for you to do at a slower pace, bad for you to try on your big bike. If you know someone with a beat bike 125, 100 or 150 then you can use that. Gear up and crash away. IMO again it will give you that feel for proper backing technique, the ass lifting a tad while heaving braking is normal, practice to balance the two, the third element in this is to pull in your clutch.

Any surface is unpredictable, you can come up to a small sliver of loose gravel, loose pavement, a cup or bump and the front is going to react accordingly. But again I ask
What is your purpose or what do you expect to achieve by doing this?

 

[sanjuro]

What is your purpose or what do you expect to achieve by doing this?

IMO locking the front is a disastrous move or reason to try. Good for you to do at a slower pace, bad for you to try on your big bike. If you know someone with a beat bike 125, 100 or 150 then you can use that. Gear up and crash away. IMO again it will give you that feel for proper backing technique, the ass lifting a tad while heaving braking is normal, practice to balance the two, the third element in this is to pull in your clutch.

Any surface is unpredictable, you can come up to a small sliver of loose gravel, loose pavement, a cup or bump and the front is going to react accordingly. But again I ask
What is your purpose or what do you expect to achieve by doing this?

He wants to know the limits of his bike and his skill.

 

[SFSV650]

What is your purpose or what do you expect to achieve by doing this?

For my part: I'm a new rider and I want to know how fast I can safely stop if things get ugly, rather than figuring it out in the heat of the moment or holding back more than I need to for fear of locking a wheel.

What I found out: I can pull the brake harder and stop in a shorter distance than I thought.

 

[p4i1]

What is your purpose or what do you expect to achieve by doing this?

I practiced emergency braking and was looking for right indicators that I am close to the limit. Initially I was thinking that locked front would be that indicator, but after this discussion I figured that very slight stoppie is the right one if progressive braking done right.

 

[ScottRNelson]

I practiced emergency braking and was looking for right indicators that I am close to the limit. Initially I was thinking that locked front would be that indicator, but after this discussion I figured that very slight stoppie is the right one if progressive braking done right.

You can do the math to determine how good your braking is. You want to have a deceleration rate 0f 0.8g or better. If you're doing it from a particular speed (25 mph is good for learning), you can measure and mark off the points where you would stop at 1.0, 0.9, 0.8 and so on to see how you're doing.

The math is at the end of this article:
http://msgroup.org/Tip.aspx?Num=032

Other tips on braking may be found here:
http://msgroup.org/Articles.aspx?Cat=2

The reason why 25 mph is good is because at that speed you can make a mistake and still not go down, or if you make a bad enough mistake and go down, you won't slide too far. It is still fast enough to get a good feel for braking near the limit, though.

 

[DocWong]

This is of course not the most effective way to shorten stopping distances, but if your goal is to lock up the front wheel and not do a stoppie:

At a moderate speed, suddenly pull very hard and very fast. You can get the front wheel to lock up sooner that way because time was to allowed for the suspension to load up the front wheel increasing traction. This is something we do at every dual sport clinic I do. It's in the dirt, so it slides the front wheel easier.

Caveat : You can easily crash doing the above on the street with high traction conditions. I.e. good sticky pavement. If the pavement is looser, such as dirt, it'll lock up easier.

Also, you must either be very light on the handle bars or put exact even pressure on them to not tweak the handlebars to not crash.

Once you feel/hear the front wheel slide, let go. You'll be glad you did.

Anyway I cover this in detail in my new Doc Wong Braking Class.

I was practicing my emergency braking today. Empty straight road, dry, clean pavement, ~30-35 mph speed. Stopping to 0 with both brakes.

So... I was thinking I would try to brake as hard until front locks to try modulating it. But I was not able to lock it . Instead my rear was up in the air just a little bit and locked. Flipping the bike or doing and stoppies were not in my plans today. And pulling front brake more rapidly and harder is too scary.

My question to those who know - how hard to lock the front on DRY, CLEAN ASPHALT without making a stoppie?