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Discussion Starter · #1 ·
Would have put another 'p' in the subject but that would make it STOP(pies), and that's just not right.

Got a question about stoppies. What makes the front wheel lock up? Is it the suspension bottoming out, or is it just plain possible to lock up the front under extreme braking?

Cheerz all.
 

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weight transfer is what causes stoppies (which is suspension and yes, it's bottomed out and the weight is transferring forward too fast). you can carry the rear wheel under braking without ever stopping.

you can lock up a front tire, but under extreme braking it is difficult.

if you transfer weight to the front, you can pull the lever to the grip and not lock it up. but as the weight transfer back, you risk locking it.

does any of that make sense? btw, some of this is my theory, so don't take it as law.
 

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I agree with you Tony. The faster you are going, the harder you can grab the brakes and not lock it up, but the slower you're going, there will be less weight up front, so the wheel will lock. So it's much better to practice stoppies at 50mph than it is at 20.

Trevor
 

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Discussion Starter · #4 ·
You say weight transfer is what causes stoppies. Here's what I understand about braking, can you please fit in where stoppies are? :)

When you brake you get the weight transfer to the front wheel. When this happens the front suspension dives. If you grab the brakes the front will dive very rapidly, bottom out, and rebound. When it rebounds there is no weight on the front wheel and it locks up. This is of course why you must allow time for the weight transfer to take place.

Where does a stoppie fit into this equation? Is it that you compress the front forks so much that they bottom out and the front cannot go any futher downward, so the back comes up?

I can do small stoppies at a maximum initiation speed (I'm too chicken to try any faster at this stage) of 40kph by getting on the brakes (to achieve the weight transfer) then really braking hard. I'm going slow enough that if the front locks up the bike will skid about two inches and stop. I'm rather lothe to try them at faster speeds, even though I had heard the logic ;)

Cheerz all.
 

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In short - to do rolling stoppies, depending how long I want to do one - I come in anywhere from 60 to 80 mhp. I go from accelerating to decelerating immeditaley. From gas to brakes right away. The first motion is to bottom out the front suspension with hard braking. Once that is done and all the weight is on the front end and it is pinned down, I add a little more pressure to the front brake and then the rear comes up. After that it's just a matter of modulation the front brake to get it up as high as you want and to keep it there. The higher you get the rear the longer the stoppie will be because less energy is put into the front brakes in order to keep the rear end up. Once you've done it a few times you will find they are very easy to do, you just need to make sure you've got the correct front tire pressure (32 psi for me) and the tires are good and warm AND the road is nice, flat and smooth.

Occasionally I try to get the rear up too fast and hit the brakes too hard before the forks are bottomed out... This causes the front end to slide b/c as you said yourself the suspesion starts to rebound and gives the tire a chance to exceed it's limit of adhesion due to lack of pressure and contact area.
 

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Stoppies

All good information so far... there is one thing to add tho... at speed (50mph) and above simply grabbing a ton of front brake, even allowing for weight transfer time, can result in locking the front wheel. So to aid the weight transfer process I follow the suspension as it compresses with adding my weight through my arms to the handlebars. This puts max weight on that front wheel when the forks hit bottom and "loads" the front end with every ounce of weight available. The bike's and my own body weight.
 

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Re: Stoppies

Bikenut said:
. So to aid the weight transfer process I follow the suspension as it compresses with adding my weight through my arms to the handlebars. This puts max weight on that front wheel when the forks hit bottom and "loads" the front end with every ounce of weight available.
What I need to know is how do I load my pants, with enough balls, to put all this theory into practice.

I'll admit it, I am afraid to do a stoppie. I am afraid the bike will not hold a straight line and will jack knife.
 

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Bikenut

Well ya.. jacknifing can be a bit of a problem if ya don't make sure the bike is in a straight line before initiating the stoppie.... but minor jacknifing can be controlled with side to side body weight transfers through the handlebars.. basically you are using the handlebars as a lever to hold the bike straight or to move the bike back into line once the stoppie is started.... as for finding the balls to do this???? Nothing ventured, nothing gained... start out at slow speeds and see what happens... pay attention to what you did and how the bike reacted to that... if you got a response you didn't like do something different the next time....

Riding is 90% mental and 10% physical skills. That holds true for doing the fun stuff and for everyday riding. Think the thing through first, then try it.
 

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Discussion Starter · #9 ·
Re: Re: Stoppies

swdunn said:

I'll admit it, I am afraid to do a stoppie. I am afraid the bike will not hold a straight line and will jack knife.
What a friend advised me to do is take all the fairings off my bike and go for it. Sounded like a whole lot of work, and I've never come close to dropping the bike ... so I never did. But if you're paranoid ...

I started out trying stoppies at relatively slow speeds - 20-30kph. Now people will tell you start big - 50-60k's, but for the inexperienced, putting on that much front brake at that sort of speed can be quite nerveracking. The reason they say start big is that if the front locks up, you've got the speed to let the front off and recover. In my experience however if you lock up the front you'll either be going fast enough to get the front to spin up again, or at a speed where if the front locks up you're virtually stopped by the time you realise it anyway and there is no drama. It would all depend on how quickly you realise that you've locked the front and get off the brake. I'm quite happy with locking up the front (as long as I'm goin' in a straight line), and recovering - it's no drama for me. If you feel that sort of confidence you won't have a problem.

Just make sure that you're sitting very snugly behind the tank, otherwise you're balls ain't gonna like you!

Safe riding!
 
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