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-   -   Decreasing radius corners (https://www.ft86club.com/forums/showthread.php?t=50854)

ZionsWrath 11-07-2013 12:58 AM

Decreasing radius corners
 
Have been practicing my heel toe and feel decent with it now in a straight line. But now my problem is decreasing radius corners. It seems some lateral force of cornering makes it hard for me to modulate the pedals. For example corner starts at around third gear ~70 and by the time I'm off the brakes is ~35, so I am trying to hit second gear.

Is it just simply a practice practice practice thing? Any tips?

Tgionet 11-07-2013 02:58 AM

I'm having trouble conceptualizing what you're trying to do. If you're talking about heel and toeing while trail braking, don't bother with it. You'll do much better braking harder while pointing straight and getting the car set up before you enter the corner. If you're having trouble on corner exit, turn in later.

There a golden rule of motorcycling that really applies across all disciplines of racing.
"Once the throttle is cracked open it is rolled on smoothly and continuously throughout the remainder of the turn."

ZionsWrath 11-07-2013 03:16 AM

You are exactly right, I downshift to the entry speed gear and am trying to downshift again during the turn so I can be in the proper gear for the exit speed.

Tgionet 11-07-2013 03:27 AM

You don't want to be shifting at all while turning. Upshifting can cause snap oversteer at the limit while the rears are likely to lock when you downshift. Coming out of a corner you want to be in the proper gear to hit redline at the end of track out. If at any point durning the corner you hit redline you'll want to take it one gear higher

atledreier 11-07-2013 03:35 AM

On "my" track we have a tricky corner with a steep downhill braking and turn-in that tightens throughout the corner, along with the compression of coming out of the downhill and starting the ascent. I basically brake HARD in the straight bit and then turn in while trailbraking. I don't have time and skill enough to do any heel-n-toe in that situation, and I'm doing fine.

This is the entry to the first part of the corner:
[ame="http://www.youtube.com/watch?v=4iOxAz2T0i0"]NM racing GT serie nye rudskogen 2011 angsten 2 - YouTube[/ame]

Incar a few years back, not in the '86, though.
[ame]http://youtu.be/Cv2QSOvmz1c?t=24s[/ame]

Incar with the '86. Har to see the road, but you can see what I'm doing. I have logs from the run if you're interested. Sorry about the camera. (1:10 in this video, start time doesn't work for some reason)
[ame]http://youtu.be/SoRZtuxWMS8?t=70s[/ame]

Here's the trackmap. We're talking about T3 and T4 which are taken as one corner.
http://shortcarracing.no/wp-content/...udskogen-1.jpg

revlimit 11-07-2013 03:58 AM

@atledreir, I think you are hijacking this thread, but you can see that that the other cars get 2 downshifts in a straight line. You are only at 5k rpm on your first downshift, you need to get another downshift while still in a straight line. It's a long brake zone, you have plenty of time. You're still slowing down at the second downshift and if you were going "fast" you'd be upsetting the car.

I imagine the same applies to OP.

juliog 11-07-2013 04:43 AM

Why is this thread, of all things, in off-topic?

7thgear 11-07-2013 10:11 AM

man that VW driver is horrible

amazing track though

7thgear 11-07-2013 10:25 AM

two ways to handle a decreasing radius turn to maximize efficiency.. and they depend on what type of corner follows this corner.

if the corner is followed by another corner, then you brake during cornernering (trial braking)

if the corner is followed by a straight, then you simply turn the decreasing radius corner into a constant radius corner.... (see below)


Trailbraking is difficult to do right and requires the most skill, you do some of your braking in the straight line coming up to the turn but then use the initial wide part to continue to slow down (with the brake) until the "exit portion" aligns itself to your speed and trajectory... in the image blow, imagine the red line, but you're braking during most of it so that when you get to the right side you're pointing down into the right direction and can get back on the gas.

if you start at 70 and end at 35, consider heel-towing into 2nd before you start your turning... also a clutch kick and a proper shift are two different things, you can shift mid corner, just do it gently

if you've got a straight after this, then you need to maximize exit speed and for this you create your own "perfect corner" on top of the existing, physical corner

you do this by staying wide and bombing deep into the corner, creating imaginary apexes for yourself........... i'm having a hard time explaining this, better in person, but here is a picture... the green line is what you're aiming for

http://image.sportrider.com/f/179797...approaches.jpg

Atropine 11-07-2013 11:33 AM

@7th Gear

Perfect...I was gonna say the classic...

"Sacrifice entrance speed for exit speed"

Your diagram shows that perfectly/ I do a lotta canyon/mountain roads.

you instinct/vision makes you see the beginning line and take it too fast. Once you come up on the decreasing radius you realize you have to scrub too much speed. On a motorcycle, this is a terrifying conclusion.

You have to use your road/track knowledge to take the proper line.
Great post...illustrates it perfectly.

fatoni 11-08-2013 01:46 PM

Quote:

Originally Posted by 7thgear (Post 1317818)
two ways to handle a decreasing radius turn to maximize efficiency.. and they depend on what type of corner follows this corner.

if the corner is followed by another corner, then you brake during cornernering (trial braking)

if the corner is followed by a straight, then you simply turn the decreasing radius corner into a constant radius corner.... (see below)


Trailbraking is difficult to do right and requires the most skill, you do some of your braking in the straight line coming up to the turn but then use the initial wide part to continue to slow down (with the brake) until the "exit portion" aligns itself to your speed and trajectory... in the image blow, imagine the red line, but you're braking during most of it so that when you get to the right side you're pointing down into the right direction and can get back on the gas.

if you start at 70 and end at 35, consider heel-towing into 2nd before you start your turning... also a clutch kick and a proper shift are two different things, you can shift mid corner, just do it gently

if you've got a straight after this, then you need to maximize exit speed and for this you create your own "perfect corner" on top of the existing, physical corner

you do this by staying wide and bombing deep into the corner, creating imaginary apexes for yourself........... i'm having a hard time explaining this, better in person, but here is a picture... the green line is what you're aiming for

http://image.sportrider.com/f/179797...approaches.jpg

i think youre ignoring the initial issue in that its not that easy to be going 70 in 2nd gear. if that was possible i dont think he would be having a problem.

7thgear 11-08-2013 01:54 PM

Quote:

Originally Posted by fatoni (Post 1320338)
i think youre ignoring the initial issue in that its not that easy to be going 70 in 2nd gear. if that was possible i dont think he would be having a problem.

i'd like to see the specific course in question... but i would say if the difference is that drastic then simply shift mid corner, if he's going all the way down to 35mph then there is little risk of clutch kicking even if he does fumble it

just blip the throttle hard and you'll be fine

Frost 11-08-2013 02:29 PM

Quote:

Originally Posted by 7thgear (Post 1317818)

That double apex line will kill your brakes and tyres in no time! I keep looking at it at going "ugh".

7thgear 11-08-2013 02:39 PM

Quote:

Originally Posted by Frost (Post 1320429)
That double apex line will kill your brakes and tyres in no time! I keep looking at it at going "ugh".

during lapping yeah it will kill you, but might be a good aggressive passing line... maybe? i don't do door-to-door racing :/


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