Street Skills Information to keep you from rashing your bike or yourself. Safe riding techniques only please.

What do you do? #1

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  #11  
Old 05-29-2012, 01:14 PM
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Originally Posted by vfrman
No it won't. More gas WILL shift the CG to the rear, putting more traction to the rear tire while at the same time increasing ground clearance at the front end. The drive forces at the rear wheel will also raise ground clearance at the rear end.

Also more gas means more velocity, which means more traction/lean angle to keep the same radius.

Kuro did the right thing (well, one of them). Using the rear brake while cornering helps scrub speed and tighten the line (reduce radius) with minimal upsetting of the chassis.
You clearly don't fully understand the results of the intended effect.
 
  #12  
Old 05-30-2012, 01:04 AM
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No, I think I understand them.

First I am going to make a few assumptions...

I assume Kuro performed the proper slow, look, press, roll technique (taught by the MSF) for what he assumed was a constant radius corner. I also assume that during the roll step, he added enough "maintenance" throttle to keep his velocity constant, meaning he was neither engine braking or accelerating in the corner.

Now in the MSF Beginner course students are taught to do all of the slowing before the corner. This is because the MSF doesn’t want to introduce an advanced technique to students who are just beginning to ride. However, in the MSF Military Sport Bike Course, trail braking techniques are introduced. Trail braking is nothing more than staying on the brakes as you approach the apex of a corner, as lean angle increases, braking must decrease, or trail off.

There is a finite amount of traction available at either tire, and this traction is either for accelerating, turning, or braking. If you add force in one area (like turning) you must subtract it from another (like braking). There is a great example of this in Sport Riding Techniques by Nick Ienatsch. The publisher even used the diagram of this technique on the cover (Amazon.com: Sport Riding Techniques: How To Develop Real World Skills for Speed, Safety, and Confidence on the Street and Track (9781893618077): Nick Ienatsch, Kenny Roberts: Books). You can see where braking percentage trails off from 70% at the beginning of the turn to 0% at the apex and then how throttle is applied at corner exit.

As far as raising ground clearance goes, adding throttle will shift the CG to the rear of the bike, which increases ground clearance at the front end. I think you are having issue with my explanation of how the rear clearance increases. When the bike accelerates, the force is at the rear tire, driving the bike forward. This forward drive tries to push the rear wheel to the front. This force travels up the swingarm to the pivot and shock, which extends, allowing wheelbase to shorten (even if only fractionally) and raise the rear of the bike. Now I will admit, this only works incrementally and if the acceleration is too great, the rearward transfer of weight will override this effect and the bike will squat. So, to be clear, this gain in rear ground clearance only happens at maintenance throttle or with very slight acceleration.

I also still stand by my statement the Kuro did the right thing by applying the rear brake. In fact, if you look in the book Sport Riding Techniques on pg 38 Nick talks about tightening the line by guess what… the rear brake.
 

Last edited by vfrman; 05-30-2012 at 01:53 AM. Reason: Added explanation
  #13  
Old 05-30-2012, 03:41 AM
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Woulda been cool to have a video goin
 
  #14  
Old 05-30-2012, 12:51 PM
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Flip traction control off, giv'er some juice, and let that back end drift around the corner .
 
  #15  
Old 05-30-2012, 01:47 PM
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Using the rear break CAN be used to tighten a turn, but it isn't and shouldn't be the first method you go for.

Trail breaking as discussed can be very efficient and many Pro's / schools teach and use it effectively. I for one use it, especially when i'm overcooking a turn (not that I ever do that b/c i'm perfect).

Most of the time you just need to trust the Motorcycle God. YOU are the limiting factor 99% of the time on a turn. Look where you want to go, say a little prayer to the MG and lo and behold.... most of the time you make it. Having good body position will help as you will have more lean angle / counter steer available.

DammitMike saw me in a decent little prayer session a couple weeks ago(211). hahah
 
  #16  
Old 05-30-2012, 06:21 PM
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Trail braking...the means to use the rear brakes & the throttle at the same time. Frankly, I do that a lot...I don't think about it though, I just know I'm going in a turn too hot....for me, it orginated from the need to flash my brake light so whomever behind me sees

an example in cars....drifting
 
  #17  
Old 05-30-2012, 06:32 PM
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Originally Posted by estate4life
Trail braking...the means to use the rear brakes & the throttle at the same time. Frankly, I do that a lot...I don't think about it though, I just know I'm going in a turn too hot....for me, it orginated from the need to flash my brake light so whomever behind me sees

an example in cars....drifting
No.... Trail braking is holding application of the front brake as you're entering the turn. As your lean angle increases as you get closer to the APEX of the turn, your level of grip decreases.

As this happens you have to lessen your application of the front brake.

Decreasing the amount of braking applied as you get closer to the Apex, eventually letting off the brake and ideally getting back into the throttle.

Coasting(bike moving forward with no break / throttle applied) is a non-desired method of movement.

Trail braking has ZERO to do with the rear brake
 

Last edited by NateDieselF4i; 05-30-2012 at 07:33 PM. Reason: Clarity / Spelling
  #18  
Old 05-30-2012, 06:40 PM
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I was under the assumption you're supposed to add REAR braking and not FRONT braking when going into a decreasing radius turn and applying gas at the same time?

Yikes. If that's not the case, then I've gotten very lucky. I once had a very similar experience to Kuro and I lightly pressed the rear brake and gave the bike gas.

Now I think about it, it seems slightly counter intuitive..but it does allow for finer precision in the amount of acceleration you give, no?
 
  #19  
Old 05-30-2012, 07:01 PM
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Now, I'm really lost.... I just ride without thinking too much. If you approach a turn correctly, we wouldn't be talking about trail braking....

So trail brakingng is prior entering a lean...I was under to impression that you already into a lean...
 
  #20  
Old 05-31-2012, 12:37 AM
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Yeah..I don't know anymore. I'm just as lost and confused as you are.

Like you said, when we ride...we just ride without thinking about what we're doing..just what needs to happen. It's instinct.
 



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