Anyone have Hub Flex?
11-16-2006, 06:13 PM
#1
Nordschleife Master
Thread Starter
Anyone have Hub Flex?
As it was explained to me by the MY350Z forum member.
I have never myself seen anyone post up on our cars having this issue but it doesn't mean it does not exist. Just like to hear peoples thoughts or opinions about it on our cars. I know that pelican sells upgraded hubs is it for this reason or another?
Originally Posted by Joel Gat
it's simple that the hubs flex when you have good traction and you drive hard. That flex translates to the rotor moving side to side in the caliper, while you're cornering and not on the brakes. That side to side motion pushes the pads away from the rotor. They end up moving less than a millimeter from the rotor surface. You go to hit your brakes and instead of the brake fluid moving the pistons just a hair, they have to move that fraction of a millimeter, which means your foot sinks almost all the way down to the floor as you take up that little amount of space.
Joel
Joel
11-16-2006, 09:42 PM
#5
Nordschleife Master
Thread Starter
Originally Posted by ninefiveone
It happens with our cars. It happens with most cars.
11-16-2006, 09:47 PM
#6
Thefu
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One potential cure is to use floating rotors ala VCI.
http://www.vehiclecraft.com/Brakes/rot_ques.htm
http://www.vehiclecraft.com/Brakes/rot_ques.htm
11-16-2006, 09:59 PM
#7
Nordschleife Master
I've experienced chub flex.
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11-17-2006, 12:15 AM
#8
You should ask the guys over on the track forum. When I used to DE my car, I never ran into such a problem. I did see a few people lose braking by boiling the brake fluid - hence the need for hi temp racing brake fluid at the track. I suppose if your car has excessively worn rear wheel bearings it could be an issue...
11-17-2006, 12:32 AM
#9
Also referred to as "knockback". I wouldn't say it's common, but it's not unheard of either.
http://www.stoptech.com/tech_info/wp_knockback.shtml
When watching race video of drivers, you can see some drivers tap their brake pedal with their left foot just prior to the braking zone. This pushes the pistons/pads closer to the rotor for better braking.
Watch this video. Not only is this the tastiest bit of driving I've ever witnessed at WGI, but if you can peel your eyes away from the windshield for a moment, watch Leh's left foot pump the brakes up on the straights.
http://gscdownloads.com/race.wmv
http://www.stoptech.com/tech_info/wp_knockback.shtml
When watching race video of drivers, you can see some drivers tap their brake pedal with their left foot just prior to the braking zone. This pushes the pistons/pads closer to the rotor for better braking.
Watch this video. Not only is this the tastiest bit of driving I've ever witnessed at WGI, but if you can peel your eyes away from the windshield for a moment, watch Leh's left foot pump the brakes up on the straights.
http://gscdownloads.com/race.wmv
11-17-2006, 02:58 AM
#10
RL Community Team
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Holy Heck Jim!
That video is fantastic, well work the wait to download. Thanks! I cannot believe how fast he is with the clutch and gearchange... mindblowing to me... Is that a cup car?
I did see the "brake pumping" that you are referring to. It amazes me how some people can drive so well and keep so many things in mind. It seemed was way faster than everyone else on that track...
That video is fantastic, well work the wait to download. Thanks! I cannot believe how fast he is with the clutch and gearchange... mindblowing to me... Is that a cup car?
I did see the "brake pumping" that you are referring to. It amazes me how some people can drive so well and keep so many things in mind. It seemed was way faster than everyone else on that track...
11-17-2006, 10:59 AM
#11
Originally Posted by amjf088
Holy Heck Jim!
That video is fantastic, well work the wait to download. Thanks! I cannot believe how fast he is with the clutch and gearchange... mindblowing to me... Is that a cup car?
I did see the "brake pumping" that you are referring to. It amazes me how some people can drive so well and keep so many things in mind. It seemed was way faster than everyone else on that track...
That video is fantastic, well work the wait to download. Thanks! I cannot believe how fast he is with the clutch and gearchange... mindblowing to me... Is that a cup car?
I did see the "brake pumping" that you are referring to. It amazes me how some people can drive so well and keep so many things in mind. It seemed was way faster than everyone else on that track...
That car was a 2002RS, slightly tweaked but nothing crazy, 420 rwhp.
In that race video, he started last due to a qualifying technicality. He passed 25 cars in the first lap alone, and won the race by 23 seconds over the second place car. He's got more driving talent in his pinky than I have overall.
And he's only 23 years old...
11-17-2006, 11:21 AM
#12
Resistance is Futile
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Originally Posted by shiners780
Also referred to as "knockback". I wouldn't say it's common, but it's not unheard of either.
http://www.stoptech.com/tech_info/wp_knockback.shtml
When watching race video of drivers, you can see some drivers tap their brake pedal with their left foot just prior to the braking zone. This pushes the pistons/pads closer to the rotor for better braking.
Watch this video. Not only is this the tastiest bit of driving I've ever witnessed at WGI, but if you can peel your eyes away from the windshield for a moment, watch Leh's left foot pump the brakes up on the straights.
http://gscdownloads.com/race.wmv
http://www.stoptech.com/tech_info/wp_knockback.shtml
When watching race video of drivers, you can see some drivers tap their brake pedal with their left foot just prior to the braking zone. This pushes the pistons/pads closer to the rotor for better braking.
Watch this video. Not only is this the tastiest bit of driving I've ever witnessed at WGI, but if you can peel your eyes away from the windshield for a moment, watch Leh's left foot pump the brakes up on the straights.
http://gscdownloads.com/race.wmv
11-17-2006, 11:22 AM
#13
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I run R compunds on the track and I've never had a problem with that. The brakes are always solid (except when the fluid gets hot).
11-17-2006, 01:03 PM
#14
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Originally Posted by Fishey
Yea, but to the extent that you lose half a pedal when trying to hit the brakes after running the car? I have never witnessed this myself.
I've gotten in the habit of giving them a tap before certain corners where I know they might have gotten knocked back. It just becomes part of the heel-toe footwork like doing the salsa.
11-17-2006, 08:02 PM
#15
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If you've ever bumped a track curb a little too hard, you've probably experienced it in the following turn. The play in the front bearing allows the rotor to push the pads in a little further, and it's a sinking feeling when the first application of the STOP pedal does nothing!
Aside from that, it is indeed some fancy footwork in that video! I'm amazed!
Aside from that, it is indeed some fancy footwork in that video! I'm amazed!