Tapping the brakes on the straights

[CL65 Captain]

This was an interesting video that was passed on to me. Of notice is the driver taps the brake pedal with his left foot on each straight to check to make sure he still has a stiff pedal before having to find out that he doesn't while threshold braking on the next corner.

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Never noticed it before.... this guy is doing the same.

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[jtower]

cool video, cmp is my second "home track" (vir being #1) and 1:32 a is damn fast lap. ISTR that billy did a 1:30.x in the cricket nsx which is even sillier, even the fairly fast guys i run with in corvettes on hoosiers rarely crack 1:40.

i thought it was interesting that the porsche driver wasn't left foot braking in turns that didn't require a downshift (turn 3, 12, and the kink). i started LFB this year and although i'm still developing the necessary sensitivity in my left foot it's helped quite a bit. here's a video showing some advanced footwork, not only does the driver LFB when shifts are not needed but he sometimes snaps off a H&T downshift then changes his braking foot. tricky.

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[angus]

I have seen and heard of this before, I think it depends on:

a)how expensive your car is

b) how many times you have crashed due to brake failure...

 

[Cody@LoveFab]

I found myself doing this last season because my brakes sucked and would routinely run to the floor.

This year when I was pushing the car, I would "pump em' up" out of habit I guess. It really is nice to know where your pedal is coming into a hairpin at 130mph.

 

[Hrant]

NASCAR drivers do it regularly :wink:

 

[MetalSpikeRacing]

I did that in the last three track events I had, Because I really wanst sure if I would have brakes or not.

Because of this:
http://www.nsxprime.com/forums/showthread.php?t=140172


-MSR

 

[NSX 3.0]

A few of my Instructors in the past always did this and I started a couple years back. Cory Friedman is one hell of a driver !

 

[R13]

Yup, I developped this habit during probably my second track weekend and have used it ever since. It bailed me out going into T1 last time I was at VIR. I had nothing, but managed to downshift, pump the pedal, and have a controlled off where there was lots of room as opposed to having to commit to the turn and possible spin off the track.

 

[92 white 0650]

Re: Worried about brakes???

For daily drivers at a track day, I can understand. But for full prepped race cars? They better do something. I can't see allowing anything to take away from total concentration (outside the car) during a race or race session. Brakes get the same priority attention as a nut and bolt check before each race.

 

[pgilliam1]

I don't understand why anyone would think they would experience brake failure on a straight after just using them the turn before. Not often do brakes fail completely from one turn to the next? They usually will give you some indication of weakening before they flat out fail. I don't get it, but then again I've never had a brake system that just stopped working all of a sudden either ?

 

[SFDreamer]

I was taught to do this my very first track instruction. Have done it ever since. A GT3 Cup Car showed up to a track day on Thursday and he was doing the same. People in the grandstands asked why they saw his brake lights on the front straight, so I explained it to them.

 

[R13]

I don't understand why anyone would think they would experience brake failure on a straight after just using them the turn before. Not often do brakes fail completely from one turn to the next? They usually will give you some indication of weakening before they flat out fail. I don't get it, but then again I've never had a brake system that just stopped working all of a sudden either ?

In my case the system apparently had a bubble in it and the fluid just cooked with the air in the system or the bubble(s) made it to the calipers braking before the "rollercoaster" at VIR, so I had nothing going into T1. It was pretty solid right up to that point so there was no way to tell. That whole weekend was a bit wierd really.

Could it have been avoided by more thorough bleeding: maybe . Does sh!t just happen sometimes: definitely.

I suppose if I were competing for money or something I wouldn't want to scrub the tiny amount of speed that tapping probably does, but I'm not so I'd rather be safe than sorry.

 

[whrdnsx]

sometimes it's a pad knock off issue which pushes the Brake pistons back just enough that the pedal may be longer than normal on the first application. The Driver will give the pedal a couple of taps just regain lost pressure. it's probably more of a psychological thing. see it a lot in racing.

 

[NSXLuvr]

I usually do this "test" on my car after fresh pads, brake flush, and 1st session.

 

[honda_pwr]

The pros do this when racing with race pads. Since they don't grip very well when they are cool, drivers tap the breaks on the straights to put some heat into them. First time I heard of this was quite a while ago on one of the Best Motoring shows.

 

[Nukem]

looks like left foot braking. I think it would be hard to get in the habit or tap the brakes light enough to keep from slowing the car down in the middle of a straight, but hard enough to tell your brakes work. Then again it took me awhile to get use to heal-toe.

 

[angus]

sometimes it's a pad knock off issue which pushes the Brake pistons back just enough that the pedal may be longer than normal on the first application. The Driver will give the pedal a couple of taps just regain lost pressure. it's probably more of a psychological thing. see it a lot in racing.

Yes pad knockback is a real issue too.

 

[sadlerau]

I had total brake failure in my race Civic several years back. Longest straight on the track, pulling 125mph went for the brakes and a piston seal let go! Ended up 10 feet away from the perimeter fence after a LONG journey through the sand trap. Not nice. :redface:

For the next few years started left foot tapping the brake pedal, ever so lightly coming up to each major braking zone. :biggrin: Finally starting to loose that bad habit. You should only do it if you have pad knock off, or the brakes don't feel 100%. Either way, you should fix the problem.

 

[scottjua]

I generally do this down a straight to fight pad knock back in my STi... especially as the pads start to get thin. I want to make sure when I go for the brakes that the dead travel doesn't put me in the weeds.

 

[Edo]

The left foot brake pedal tap is done for one reason.
To take up any pad knockback that might have occured.

Using your left foot to "check" to make sure you have brakes is not conducive to driving fast as you'd have to push hard enough to actually slow the car down for it to be of any real use.

Anytime your car runs over bumpy area's or curbing the brake pistons will get knocked back some, giving you a mushy pedal feel. Tapping the brakes with your left foot will remove this slack giving you a consistent brake pedal application every time.