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I am glad you can, I have the bars against the stop and I cannot stay in the circle
 
I agree Dobs and if I try to lean any harder it heads straight for the pavement. After catching it twice at the point of no return and getting it back up, I quit trying. Both times there were people there to help me hold it and get it back up straight.

About once a month or so a group of us go out and practice slow speed stuff.
 
I have yet to try a motorcycle that didn't get tippy right at the steering stop. There's a fine line at that point between carrying enough momentum not to tip and not going too fast to keep it turned.
 
Discussion starter · #26 ·
I have yet to try a motorcycle that didn't get tippy right at the steering stop. There's a fine line at that point between carrying enough momentum not to tip and not going too fast to keep it turned.
Ah yes, a u turn at full steering lock is very difficult on a sportbike. Seems easier to do on a normal commuter bike like the school bikes i used while learning. Phaps the riding posture also plays a part??

Im sometimes successful with it on a sportbike but not always. Theres as you say a happy throttle point where it just goes so well, but not easy to get it all the time.

Most often i tend to go a little too wide. I had been told that i need to counterbalance to get the radius tighter. But seems so counter intuitive!!
 
Ah yes, a u turn at full steering lock is very difficult on a sportbike. Seems easier to do on a normal commuter bike like the school bikes i used while learning. Phaps the riding posture also plays a part??

Im sometimes successful with it on a sportbike but not always. Theres as you say a happy throttle point where it just goes so well, but not easy to get it all the time.

Most often i tend to go a little too wide. I had been told that i need to counterbalance to get the radius tighter. But seems so counter intuitive!!
I agree Dobs and if I try to lean any harder it heads straight for the pavement. After catching it twice at the point of no return and getting it back up, I quit trying. Both times there were people there to help me hold it and get it back up straight.

About once a month or so a group of us go out and practice slow speed stuff.
Counterbalancing! Are you trying that, Critter? I have seen some seriously huge bikes turned on a freakin dime using that technique.
 
You also need to turn your head to where you want to go. Not where you are presently going.

Next time you have trouble, force yourself to turn back nearly where you came from. It's not an easy thing to do because you just know you will fall over. But chances are real good you won't and you'll make the turn you once thought you couldn't.

I know it's hard to turn away like that. You want to go where you think you are going but you just aren't looking far enough in most cases.
 
Well...yeah. See, when you're moving, you have kinetic force, in the form of what is called "momentum". When you suddenly try to stop, that momentum has to be dispersed. Typically gradually.

When you apply any braking, you create the force of resistance, which works to disperse the momentum. This is typically done gradually, to slowly reduce the momentum until the force of resistance is stronger than the force of momentum, causing a complete stop.

When you brake from the front really hard, the front wheel quickly loses momentum, and gains resistance, but the rear wheel does not. And so it tries to continue moving, even as the front tries to stop. The back of the vehicle's pushed against the front. And if it pushes with enough momentum, well...that force has to go somewhere. And if the force of resistance on the front wheel is too strong to gradually break that momentum, then the momentum force literally just tries to go around it. This shows in the form of the bike sliding to one side or another, as the rear wheel tries to pass the front one.

When you apply both brakes evenly, this doesn't happen, because the momentum on the rear wheel is also being dispersed by its own source of resistance.

It should also be noted that if you use only the rear break, you will not have this problem, as the front wheel can not "push" against the back, because the source of momentum is already past the source of resistance. Instead of being "pushed" against, it's being "pulled" against. This is actually why you only get 30% of your stopping power from the rear brake. Because the momentum force can't be compressed against the solid frame of the bike. Instead, pulling against it, which is not nearly as effective as resistance.

Bottom line, whenever you can, use BOTH brakes simultaneously. You'll have a lot shorter stopping distance, and a lot safer. The front brake possesses 70% of your stopping power, while the rear only 30%. But both together holds 100% stopping power.

 
Well...yeah. See, when you're moving, you have kinetic force, in the form of what is called "momentum". When you suddenly try to stop, that momentum has to be dispersed. Typically gradually.

When you apply any braking, you create the force of resistance, which works to disperse the momentum. This is typically done gradually, to slowly reduce the momentum until the force of resistance is stronger than the force of momentum, causing a complete stop.

When you brake from the front really hard, the front wheel quickly loses momentum, and gains resistance, but the rear wheel does not. And so it tries to continue moving, even as the front tries to stop. The back of the vehicle's pushed against the front. And if it pushes with enough momentum, well...that force has to go somewhere. And if the force of resistance on the front wheel is too strong to gradually break that momentum, then the momentum force literally just tries to go around it. This shows in the form of the bike sliding to one side or another, as the rear wheel tries to pass the front one.

When you apply both brakes evenly, this doesn't happen, because the momentum on the rear wheel is also being dispersed by its own source of resistance.

It should also be noted that if you use only the rear break, you will not have this problem, as the front wheel can not "push" against the back, because the source of momentum is already past the source of resistance. Instead of being "pushed" against, it's being "pulled" against. This is actually why you only get 30% of your stopping power from the rear brake. Because the momentum force can't be compressed against the solid frame of the bike. Instead, pulling against it, which is not nearly as effective as resistance.

Bottom line, whenever you can, use BOTH brakes simultaneously. You'll have a lot shorter stopping distance, and a lot safer. The front brake possesses 70% of your stopping power, while the rear only 30%. But both together holds 100% stopping power.

Please keep track of your terminology. Force=ma but momentum=mv. Force is a rate function that describes what it takes to change momentum over time. V, velocity, is a vector function that includes speed and direction. Speed is a first derivative function of distance with respect to time. Force and acceleration are also vector functions that include the second derivative of distance with respect to time and also direction.
About all I can agree with in your post is that you should use both brakes in most situations when braking.
 
Please keep track of your terminology. Force=ma but momentum=mv. Force is a rate function that describes what it takes to change momentum over time. V, velocity, is a vector function that includes speed and direction. Speed is a first derivative function of distance with respect to time. Force and acceleration are also vector functions that include the second derivative of distance with respect to time and also direction.
About all I can agree with in your post is that you should use both brakes in most situations when braking.
Hey, I'm not a physicist, but change the terms to their proper counterparts, and it checks out. Your rear tire slides, because it's effectively trying to pass the front one.
 
Hey, I'm not a physicist, but change the terms to their proper counterparts, and it checks out. Your rear tire slides, because it's effectively trying to pass the front one.
9 times out of 10 it's sliding because you hit it too hard for conditions. Or you hit it to the point where it is almost locked and then grabbed a handful of front brake.
 
I have to agree with Critter. The rear wheel does not have a mind of its own and does not try to pass the front wheel but it can get light enough from excessive front braking to no longer have good road contact. If you do not have the rear quite that light you can still easily break it loose by applying too much rear brake. Terminology is not important here unless you know and try to follow the explanation using the principles of physics.
 
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