Double Clutch & Trail braking
09-26-2002, 01:01 AM
#16
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quote:
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Originally posted by Glen:
Mark, very nice...
Sincerely,
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Glad to try to help.
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Posts: 1013 | From: South of da Mason-Dixson |
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hmmm Very Interesting!...
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Originally posted by Glen:
Mark, very nice...
Sincerely,
--------------------------------------------------------------------------------
Glad to try to help.
--------------------------------------------------------------------------------
Posts: 1013 | From: South of da Mason-Dixson |
Registered: Apr 2002 | IP: Logged
hmmm Very Interesting!...
09-26-2002, 02:47 PM
#17
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[quote]Originally posted by Suwipin:
<strong>Hi Mark,
Thank you so much for your description and examples. That really helps me a lot in understanding more about trail braking.
</strong><hr></blockquote>
If any of you get a chance to ride with Mark, DO IT! Without his explanations of what he's doing it may be a little tough to figure out, because you won't be able to feel what he's doing.
He's smooth. Like butter on a bald monkey.
<strong>Hi Mark,
Thank you so much for your description and examples. That really helps me a lot in understanding more about trail braking.
</strong><hr></blockquote>
If any of you get a chance to ride with Mark, DO IT! Without his explanations of what he's doing it may be a little tough to figure out, because you won't be able to feel what he's doing.
He's smooth. Like butter on a bald monkey.
09-26-2002, 03:24 PM
#19
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[quote]Originally posted by E. J.:
<strong>I don't see how he reaches the pedals to even be smooth. Look how small he is from his Avatar.</strong><hr></blockquote>
I think that's an old picture. He's almost five feet tall now.
<strong>I don't see how he reaches the pedals to even be smooth. Look how small he is from his Avatar.</strong><hr></blockquote>
I think that's an old picture. He's almost five feet tall now.
09-26-2002, 03:50 PM
#20
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Silver and Mike,
Sorry for the confusion. I don't drive the car often enough and it's hard to remember what I did. I must have confused with the times when I didn't have a good blip during heel and toe and unintentional used engine brake. I normaly don't.
I used to let the car coast in neutral coming to a turn, braked during the turn, and shift into a gear when exiting. I found this is the easiest way for make a smooth turn (for beginner?) but, of course, could never be in the right gear when exiting.
Now I am learning to shift into a gear with heel and toe technic (usually 2nd), brake to slow down enough so that during the turn I don't have to brake (somtimes lighty accelerate, depends on the speed), and exiting with the car already in 2nd gear. I hope this is the right way (?).
This is for street driving only. I just want a smooth turn and exit with a perfect acceleration . It just feels good.
Thx
Sorry for the confusion. I don't drive the car often enough and it's hard to remember what I did. I must have confused with the times when I didn't have a good blip during heel and toe and unintentional used engine brake. I normaly don't.
I used to let the car coast in neutral coming to a turn, braked during the turn, and shift into a gear when exiting. I found this is the easiest way for make a smooth turn (for beginner?) but, of course, could never be in the right gear when exiting.
Now I am learning to shift into a gear with heel and toe technic (usually 2nd), brake to slow down enough so that during the turn I don't have to brake (somtimes lighty accelerate, depends on the speed), and exiting with the car already in 2nd gear. I hope this is the right way (?).
This is for street driving only. I just want a smooth turn and exit with a perfect acceleration . It just feels good.
Thx
09-26-2002, 03:55 PM
#21
Drifting
sorry for the late chime in but couple things I have to mention.
PIN, do not TRAILBRAKE.. And if you do attempt it, don't attempt it at a PCA event. Trailbraking exercises should be reserved for racing schools like skip barber where you can learn in a controlled enviorment. It is extremely easy to spin out while trail braking.
HN, NEVER, NEVER, NEVER - ENGINE BRAKE. This is commonly called TCO - Or Trailing Clutch Oversteer. Use your brakes to stop the car, not the engine. Excuse me, what I mean is, don't use the clutch to induce slight oversteer. By doing so you risk unsettling the car.
I also want to add for Pin. Double clutching is useless on your car, your have syncro's. It is helpful if you plan on racing a vintage race car but other than that, there are other skills you are better off spending your time honing. After all, if you do need to double clutch, the entire trick to tracking cars is double clutch, heel and toe downshifting, while threshold trailbraking, while hitting your apex.. Adding the double clutching only complicates the matter and is not neccessary.
If you are going to attempt trail braking (against my advice and going to racing school)
Here are a few things to keep in mind.
a)a car only has 100% grip.
--- So, if you are using 90% to brake, you can only use 10% to turn.. Or 80/20, 70/30 ETC.
b)the way to apply the ratio is: pretend there is a piece of string that is connected from the steering wheel to your foot. As you wind the steering wheel, you must lift off the brake an even value. So lets say you turn the wheel 10%, you must reduce your brake pressure by 10%.
Lets say you turn the wheel 20%, you must lift brake pressure by 20%.
Back to the piece of string. If the imaginary piece of string gets too tight because you are braking and turning too hard, you have exceded 100% grip and you will spin out. So, when the wheel turns, your foot lifts in conjuction to the input.
Again, don't try this at home, brake in a straight line. If you so desire these advanced skills like trail braking, go to racing school. It should not be done at a PCA event.
Good luck.
PIN, do not TRAILBRAKE.. And if you do attempt it, don't attempt it at a PCA event. Trailbraking exercises should be reserved for racing schools like skip barber where you can learn in a controlled enviorment. It is extremely easy to spin out while trail braking.
HN, NEVER, NEVER, NEVER - ENGINE BRAKE. This is commonly called TCO - Or Trailing Clutch Oversteer. Use your brakes to stop the car, not the engine. Excuse me, what I mean is, don't use the clutch to induce slight oversteer. By doing so you risk unsettling the car.
I also want to add for Pin. Double clutching is useless on your car, your have syncro's. It is helpful if you plan on racing a vintage race car but other than that, there are other skills you are better off spending your time honing. After all, if you do need to double clutch, the entire trick to tracking cars is double clutch, heel and toe downshifting, while threshold trailbraking, while hitting your apex.. Adding the double clutching only complicates the matter and is not neccessary.
If you are going to attempt trail braking (against my advice and going to racing school)
Here are a few things to keep in mind.
a)a car only has 100% grip.
--- So, if you are using 90% to brake, you can only use 10% to turn.. Or 80/20, 70/30 ETC.
b)the way to apply the ratio is: pretend there is a piece of string that is connected from the steering wheel to your foot. As you wind the steering wheel, you must lift off the brake an even value. So lets say you turn the wheel 10%, you must reduce your brake pressure by 10%.
Lets say you turn the wheel 20%, you must lift brake pressure by 20%.
Back to the piece of string. If the imaginary piece of string gets too tight because you are braking and turning too hard, you have exceded 100% grip and you will spin out. So, when the wheel turns, your foot lifts in conjuction to the input.
Again, don't try this at home, brake in a straight line. If you so desire these advanced skills like trail braking, go to racing school. It should not be done at a PCA event.
Good luck.
09-26-2002, 04:42 PM
#22
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[quote]Originally posted by B-Line:
<strong>sorry for the late chime in but couple things I have to mention.
PIN, do not TRAILBRAKE.. And if you do attempt it, don't attempt it at a PCA event. Trailbraking exercises should be reserved for racing schools like skip barber where you can learn in a controlled enviorment. It is extremely easy to spin out while trail braking.
</strong><hr></blockquote>
Strong disagreement from me on this one Seth. I have taught dozens fo students to trail brake at DE's and never had one spin while working on this skill. Fact is, almost everyone already trail brakes, they just don't realize it. It isn't a difficult skill and does not requie Skippy school to learn. Even if you want to take it to the limit, you can do so in a DE - find the corner you want to work and make sure you have a big space - no one in front of you and no one close behind. Not a big deal to spin when you know you have a high chance of spinning.
<strong>sorry for the late chime in but couple things I have to mention.
PIN, do not TRAILBRAKE.. And if you do attempt it, don't attempt it at a PCA event. Trailbraking exercises should be reserved for racing schools like skip barber where you can learn in a controlled enviorment. It is extremely easy to spin out while trail braking.
</strong><hr></blockquote>
Strong disagreement from me on this one Seth. I have taught dozens fo students to trail brake at DE's and never had one spin while working on this skill. Fact is, almost everyone already trail brakes, they just don't realize it. It isn't a difficult skill and does not requie Skippy school to learn. Even if you want to take it to the limit, you can do so in a DE - find the corner you want to work and make sure you have a big space - no one in front of you and no one close behind. Not a big deal to spin when you know you have a high chance of spinning.
09-26-2002, 04:58 PM
#23
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[quote]Originally posted by B-Line:
<strong>
PIN, do not TRAILBRAKE.. And if you do attempt it, don't attempt it at a PCA event. Trailbraking exercises should be reserved for racing schools like skip barber where you can learn in a controlled enviorment. It is extremely easy to spin out while trail braking.
{snip}
Again, don't try this at home, brake in a straight line. If you so desire these advanced skills like trail braking, go to racing school. It should not be done at a PCA event.
</strong><hr></blockquote>
Seth,
Why shouldn't trail braking be taught at PCA events? What is so magical about racing schools that allow this technique to be taught?
Pin,
Try it, but do so at a slower than normal speed until you are comfortable, then increase your speed gradually. Also talk to your instructor about this before you start practicing. In general novice to intermediates have other things that they should be working on first. But in certain turns trailbraking is a necessity due to the track or it lets you take advantage of the tracks configuration.
Double clutching isn't 100% neccesary. I don't do it but if you are used to it, continue to do so.
Greg
<strong>
PIN, do not TRAILBRAKE.. And if you do attempt it, don't attempt it at a PCA event. Trailbraking exercises should be reserved for racing schools like skip barber where you can learn in a controlled enviorment. It is extremely easy to spin out while trail braking.
{snip}
Again, don't try this at home, brake in a straight line. If you so desire these advanced skills like trail braking, go to racing school. It should not be done at a PCA event.
</strong><hr></blockquote>
Seth,
Why shouldn't trail braking be taught at PCA events? What is so magical about racing schools that allow this technique to be taught?
Pin,
Try it, but do so at a slower than normal speed until you are comfortable, then increase your speed gradually. Also talk to your instructor about this before you start practicing. In general novice to intermediates have other things that they should be working on first. But in certain turns trailbraking is a necessity due to the track or it lets you take advantage of the tracks configuration.
Double clutching isn't 100% neccesary. I don't do it but if you are used to it, continue to do so.
Greg
09-26-2002, 05:02 PM
#24
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I like traibraking and use it.
It makes turn in easier and while DE's are not timed event etc. I still like to go as fast as possible (maybe not 100% since it's street car but I'm there to drive as fast as I can).
However, my instructor adviced me not to do it... I did it couple of times & I did it ok, wasn't screwing up or anything but his advice was only to brake in straigt line.
I know I can do it (in some level anyway) but I'm still 'fresh' and I don't want to start arguing with my instructors, so how could I say him that this is something I've done before and I'd like to do it now also without making him to thing I'm a 'rebel' or something?
(I actually am a 'rebel' but that's another issue...
)
It makes turn in easier and while DE's are not timed event etc. I still like to go as fast as possible (maybe not 100% since it's street car but I'm there to drive as fast as I can).
However, my instructor adviced me not to do it... I did it couple of times & I did it ok, wasn't screwing up or anything but his advice was only to brake in straigt line.
I know I can do it (in some level anyway) but I'm still 'fresh' and I don't want to start arguing with my instructors, so how could I say him that this is something I've done before and I'd like to do it now also without making him to thing I'm a 'rebel' or something?
(I actually am a 'rebel' but that's another issue...
)
09-26-2002, 05:05 PM
#25
Drifting
Hey Mark,
As much as I would love to agree with you, I can't.
At every DE I have ever been to, there has always been lap traffic. I have run with over 10 groups and I have yet to be in an enviorment where even the advanced groups have the opportiunity to trail brake. What I find mostly happens is, the guy in front of you who is not trail braking or even threshold braking, is coasting into the braking zone.
But lets just say you have an open track. A student who knows how to heel n toe, threshold brake and always hits his/hers apex's. With no class room instruction, no cones, and no one standing outside the car to evaluate the technique, I still think it's a bad idea.
But Mark, my view is also skewed. I've been to PCA events and been in solo groups in the rain, I didn't see one other driver driving a rain line.
And they were spinning off the track like mad.
I am a strong advocate of racing school. It is a much more controlled, safe enviorment that teaches technique in a proven way.
As much as I would love to agree with you, I can't.
At every DE I have ever been to, there has always been lap traffic. I have run with over 10 groups and I have yet to be in an enviorment where even the advanced groups have the opportiunity to trail brake. What I find mostly happens is, the guy in front of you who is not trail braking or even threshold braking, is coasting into the braking zone.
But lets just say you have an open track. A student who knows how to heel n toe, threshold brake and always hits his/hers apex's. With no class room instruction, no cones, and no one standing outside the car to evaluate the technique, I still think it's a bad idea.
But Mark, my view is also skewed. I've been to PCA events and been in solo groups in the rain, I didn't see one other driver driving a rain line.
And they were spinning off the track like mad.
I am a strong advocate of racing school. It is a much more controlled, safe enviorment that teaches technique in a proven way.
09-26-2002, 05:14 PM
#26
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[quote]Originally posted by B-Line:
<strong>I also want to add for Pin. Double clutching is useless on your car, your [sic] have syncro's [sic].</strong><hr></blockquote>
Double-clutching is not useless. It may not be necessary, but it certainly is useful. Synchros help to synchronize the speed of the gear to the speed of the shaft by wedging the brass* synchronizer ring over a cone-shaped extension on the side of the gear. Because the gear is steel and the synchronizer ring is brass, the brass ring wears a tiny bit with each usage (through friction). That's why many transmissions have worn synchros. When one employs double-clutching, the speed differential between the gear and the shaft is greatly reduced (to near zero, if done correctly) before the synchro ever comes into play, and the synchro ring has far less speed differential to deal with, therefore, enabling the synchros to last longer.
Double-clutching is far from useless.
*racing synchro rings are steel, not brass.
<strong>I also want to add for Pin. Double clutching is useless on your car, your [sic] have syncro's [sic].</strong><hr></blockquote>
Double-clutching is not useless. It may not be necessary, but it certainly is useful. Synchros help to synchronize the speed of the gear to the speed of the shaft by wedging the brass* synchronizer ring over a cone-shaped extension on the side of the gear. Because the gear is steel and the synchronizer ring is brass, the brass ring wears a tiny bit with each usage (through friction). That's why many transmissions have worn synchros. When one employs double-clutching, the speed differential between the gear and the shaft is greatly reduced (to near zero, if done correctly) before the synchro ever comes into play, and the synchro ring has far less speed differential to deal with, therefore, enabling the synchros to last longer.
Double-clutching is far from useless.
*racing synchro rings are steel, not brass.
09-26-2002, 05:19 PM
#27
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[quote]Originally posted by B-Line:
<strong>At every DE I have ever been to, there has always been lap traffic. I have run with over 10 groups and I have yet to be in an enviorment where even the advanced groups have the opportiunity to trail brake.</strong><hr></blockquote>
LOL!
Welcome to the West Coast, Seth. I think you'll find that the "advanced groups" here are a little more advanced than what you're used to.
<strong>At every DE I have ever been to, there has always been lap traffic. I have run with over 10 groups and I have yet to be in an enviorment where even the advanced groups have the opportiunity to trail brake.</strong><hr></blockquote>
LOL!
Welcome to the West Coast, Seth. I think you'll find that the "advanced groups" here are a little more advanced than what you're used to.
09-26-2002, 05:23 PM
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[quote]Originally posted by B-Line:
<strong>
At every DE I have ever been to, there has always been lap traffic. I have run with over 10 groups and I have yet to be in an enviorment where even the advanced groups have the opportiunity to trail brake. What I find mostly happens is, the guy in front of you who is not trail braking or even threshold braking, is coasting into the braking zone.
</strong><hr></blockquote>
If you are running in the advanced groups and the guys are coasting to the turns you need to find a different group to run with or start racing. Even with traffic you can find a corner or two to work with, it is called timing. You slow down a bit to get some room and then go back at it before you catch the guy in front or someone catches you.
<strong>
At every DE I have ever been to, there has always been lap traffic. I have run with over 10 groups and I have yet to be in an enviorment where even the advanced groups have the opportiunity to trail brake. What I find mostly happens is, the guy in front of you who is not trail braking or even threshold braking, is coasting into the braking zone.
</strong><hr></blockquote>
If you are running in the advanced groups and the guys are coasting to the turns you need to find a different group to run with or start racing. Even with traffic you can find a corner or two to work with, it is called timing. You slow down a bit to get some room and then go back at it before you catch the guy in front or someone catches you.
09-26-2002, 05:41 PM
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DJ
[quote] When one employs double-clutching, the speed differential between the gear and the shaft is greatly reduced (to near zero, if done correctly) before the synchro ever comes into play, and the synchro ring has far less speed differential to deal with, therefore, enabling the synchros to last longer. <hr></blockquote>
Isn't that also true when you give a blip while single clutching? -- The speed differential is reduced to zero
I learned and raced for a couple years in a car that you had to double clutch.
I did a PDE with Hurley Haywood as the instructor. When he was in the passenger seat and I double clutched he said "what are you doing? Don't do that, a blip will suffice on cars with modern synchros."
He actually MADE me stop double-clutching, saying it was just wasting precious time.
It took three laps of Road Atlanta before I could get into the single-clutch rhythm.
I agree with Mark -- a lot of people are trail-braking without even knowing it.
Mike
[quote] When one employs double-clutching, the speed differential between the gear and the shaft is greatly reduced (to near zero, if done correctly) before the synchro ever comes into play, and the synchro ring has far less speed differential to deal with, therefore, enabling the synchros to last longer. <hr></blockquote>
Isn't that also true when you give a blip while single clutching? -- The speed differential is reduced to zero
I learned and raced for a couple years in a car that you had to double clutch.
I did a PDE with Hurley Haywood as the instructor. When he was in the passenger seat and I double clutched he said "what are you doing? Don't do that, a blip will suffice on cars with modern synchros."
He actually MADE me stop double-clutching, saying it was just wasting precious time.
It took three laps of Road Atlanta before I could get into the single-clutch rhythm.
I agree with Mark -- a lot of people are trail-braking without even knowing it.
Mike
09-26-2002, 05:57 PM
#30
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[quote]Originally posted by DJ:
<strong>
LOL!
Welcome to the West Coast, Seth. I think you'll find that the "advanced groups" here are a little more advanced than what you're used to.</strong><hr></blockquote>
Seth,
Like DJ said, Welcome to the West Coast. At many of the events here, guys are driving race cars and turning laps as fast as qualifying, often turning personal best times. In these groups, the fast group tends to be very heads up, running open passing with little need to ever get held up by a slower car. Even the middle groups are fast - passing in corners with points. Do TracQuest, sign up for the fastest group Todd will let you do and see what we mean.
<strong>
LOL!
Welcome to the West Coast, Seth. I think you'll find that the "advanced groups" here are a little more advanced than what you're used to.</strong><hr></blockquote>
Seth,
Like DJ said, Welcome to the West Coast. At many of the events here, guys are driving race cars and turning laps as fast as qualifying, often turning personal best times. In these groups, the fast group tends to be very heads up, running open passing with little need to ever get held up by a slower car. Even the middle groups are fast - passing in corners with points. Do TracQuest, sign up for the fastest group Todd will let you do and see what we mean.