Descending Technique and ACTION SHOTS

[Karvalo]

Can you confidently corner at your maximum capacity with your hands next to the stem or arms on the bar?

Neither could I confidently corner near my maximum capacity with the seatpost removed.

So the handlebar does matter and you do use it to corner. Cool, glad we're back to talking about reality.

[Karvalo]

You've argued that descending with weight on both feet is better and that weight on the outside foot is better.

You've argued that people descending outrageously fast with the knee out isn't a reason to think it's a good technique, but that your method working for you is a reason to think it's objectively good and scientifically justified.

You even just argued that Vincenzo Nibali might be simply mediocre at going round a corner.

I hope you do see those problems.

I have argued none of that. You clearly have an agenda.

You have argued all of that. Exactly that. I'm not sure why your agenda is to claim any different since it's all written down for anyone to see.

Or, meet me in Spain in August and we will race down the Angliru for pinks. What bike will you be bringing? Not going to risk it for a beater.

It's pretty clear that you've realised you position is unsupportable, but instead of simply admitting that you're trying to pretend you never made the argument in the first place. Excuse me if I wouldn't trust you to hold up your end if you lose.

[usr]

I think/hope (how much do we really _know_ about these short flashes of memory?) that my surprise dirt patch reaction is straightening the line for a meter or two: bike goes up (hip, or lateral arms, or pushing/pulling the bars, doesn't really matter, ideally all of them at once I guess), body mass remains somewhat inside the would-be balanced line of that new, temporary curve radius (but c.o.m. certainly doesn't remain on the path it would have taken on the original line, remember that we are trying to unload laterally and that original path would require countering its centrifugals). So when we get out of the dirt patch, if hopefully it ends somewhere, somewhat disbalanced. If it doesn't end, the same lateral unloading would be used as an opportunity for braking. This straightening up reaction is really the same reaction as that full "whoopsie, too fast!" that makes you lose a lot of time compared to a clean line at well selected speed, just without involving the brakes.

So back to how we get out of the dirt patch somewhat disbalanced. How much? Well, if we give the dirt patch two meters and assume 36 km/h it would be as far disbalanced as we can be after 200 milliseconds of tipping over. Not that much, really. This temporarily disbalanced state primes us to proceed on a much tighter curve radius when reestablishing normal riding position, returning to the original line. This entire approach certainly requires some reserves to be there on the happy state road surface, but that has to be a given because otherwise no athletic trick in the world could prevent wiping out (at this point the hypothetical perfect descender wouldn't waste a single reflex reaction on something that isn't softening the fall, which would probably involve the brakes, either to go down as fast as possible to maximise body/road friction if conditions next to the road are worse, or to go down as slow and late as possible, if beyond the road a nice, inviting meadow is waiting to cushion the landing)

That's the theory, so far so good. But how does it happen in reality? I certainly don't go through these considerations in a split second. But my instincts do try to avoid the problem I know (the dirt patch) and would rather risk it with a problem that I don't know yet. The curve might proceed tighter than anticipated, but who cares, dirt patch! So it comes very natural to enlist reserves that were primarily held for some other unknown for solving the problem at hand, in this case a combination of some spare room on the far end outside and extra lean post-dirt. The perfect line, to me, isn't the fastest possible line under ideal conditions, it's the line that has a reasonable amount of reserves and not far more reserves than really necessary.

[Karvalo]

It's an example of serious speed and some good turns without throwing out a knee. Just pointing out for the skeptics that it can be done, and is done.

No one said it couldn't be done. People disagree with you that knee out is the objectively worse tehnique that leads to inferior traction and control and is used by people who don't understand descending principles.

No one ever said you or anyone else couldn't descend with the knee in if you want.

[Karvalo]

Ideally you’d put more weight on both tires by getting as low as possible on the bike.

Explain further? Being low on the bike doesn't put more weight through the tyres. The process of getting low would first reduce then increase the load on the tyres very briefly, then you're back to where you started in terms of total weight.

[warthog101]

He went in too fast and had to lose too much speed.... and crashed.... slow in fast out as Kenny Roberts used to say.

King Kenny had a throttle.
You could argue he was better at being fast out than other GP racers at the time, as he was used to controlling a sliding bike with the throttle, due to his flat track racing background.

https://youtu.be/2bC2so3vp44

[usr]

Ideally you’d put more weight on both tires by getting as low as possible on the bike.

Explain further? Being low on the bike doesn't put more weight through the tyres. The process of getting low would first reduce then increase the load on the tyres very briefly, then you're back to where you started in terms of total weight.

Heh, well spotted, unless of course if there happens to be cake on the lower decks

I'm not convinced of any low/high or fore/aft approaches anyways. As long as they stay in that dynamic balance plane ("yellow line") they won't change the ratio between vertical force (provides grip) and lateral force (requires grip) at all.

[Karvalo]

I'm not convinced of any low/high or fore/aft approaches anyways. As long as they stay in that dynamic balance plane ("yellow line") they won't change the ratio between vertical force (provides grip) and lateral force (requires grip) at all.

It matters when initiating or exiting a turn, or changing line. The higher the mass is, the further it has to move to achieve the same lean angle change, therefore lower CoM is more agile.

[usr]

True, but none of that applies to the proposed dirt patch technique of dropping low to temporarily unload the contact patches without any line or angle changes.

In my personal turn movement sequence I noticed a tendency to go low in the apex of the turn, not for the unloading before but for increasing load when stopping/reversing at the lowest point. It's probably just a misperception like the "harder tires feel faster" thing, but I wonder if there could be more. Movement instincts getting ready to compensate a limited traction loss (e.g. flipping a single pebble) by explosively extending the distance from center of mass to contact patches so that c.o.m. isn't on a free straight tangential course when traction is regained?

[jasjas]

He went in too fast and had to lose too much speed.... and crashed.... slow in fast out as Kenny Roberts used to say.

King Kenny had a throttle.
You could argue he was better at being fast out than other GP racers at the time, as he was used to controlling a sliding bike with the throttle, due to his flat track racing background.

https://youtu.be/2bC2so3vp44

indeed Kenny did but the fact remains, that the guy went in too fast, tried to scrub speed and crashed... yes you need to carry corner speed on 'cycle but crashing will cost you far more time than a more conservative approach, as this guy proved.

[spud]

Ya spud that is actually very interesting.

This is actually another great rabbit hole: What's the best method for keeping the bike up when cornering into a surprise water or loose gravel on skinny road tires?

This can often happen when descending into or out of blind corners. And the rider has a split second decision to make.

So what's the best approach when faced with such scenario? Does one load more weight on the front tires? Do you let up on the grip of the front tires and give more to the rear? Even balance? Or do you do a dynamic approach, like the rider you just described -- and if so, what do those different phases look like?

In truth, every situation is unique. Many factors feed into the "correct" thing to do, and you only have your instincts to rely on. Those who have faced it the most, both pass & fail, will have the most experienced instincts. But amongst those, an even fewer subset can truly articulate their instincts in a way that can be understood and accepted by others.

Even still, stuff like this gets debated to the end of time because the correct thing to do is actually complex -- aka incredibly difficult to measure by definition... sometimes even immeasurable. Combine that with the issue of qualia, where what one individual subjectively experiences is totally different from another's, despite both people experiencing the exact same thing. Imagine one person eats an apple and tastes it sweet, while another born without all tastebuds intact only tastes tart and sour despite it being the same apple. These people end up perceiving and valuing different things from the same world they live in. But who is actually right? Or maybe they're both wrong when we bring in a 3rd supertaster? But how do we know this person is a supertaster? Maybe it's the apple who is wrong?

The crux of this entire topic.

I drag my brakes down descents, blame carbon rims when they warp and blow up, and pros actually climb mountains faster than I can descend them so you should all totally listen to me btw.

When faced with a prolonged dirt or water patch, assuming you are near the limits of cornering prior to hitting the patch, the ONLY remedy is to straighten the segment, ie open your turn so lateral acceleration drops. Going for the brakes to lower speed, and reduce lateral acceleration, while staying on the same line, will more than likely result one or both tires slipping out abruptly with little to no chance of catching it. If the patch is short, dropping center of mass during that portion may get you through it. But if you bottom on the bike before you leave the patch, it's almost certain the abrupt change in tire load will cause a crash. What that patch distance equates to is (time to drop) x velocity (f/s). Assuming it takes you 1/4 second to drop into the bike, going 30 mph, that means you can cover about 10 feet before you bottom out and load the tires up again. But I'm only guessing for the drop time, it could be shorter or longer.

[Miller]

This is all reminding me of Velominati rule #64.

[warthog101]

He went in too fast and had to lose too much speed.... and crashed.... slow in fast out as Kenny Roberts used to say.

King Kenny had a throttle.
You could argue he was better at being fast out than other GP racers at the time, as he was used to controlling a sliding bike with the throttle, due to his flat track racing background.

https://youtu.be/2bC2so3vp44

indeed Kenny did but the fact remains, that the guy went in too fast, tried to scrub speed and crashed... yes you need to carry corner speed on 'cycle but crashing will cost you far more time than a more conservative approach, as this guy proved.

There is far less control on a bicycle however without a throttle.
You are not controlling a slide or exit speed without one.
Not running soft tyres with a larger contact patch that allow the feel and control of a slide when combined with a throttle.
No ability to be particularly "fast out" without drive being applied to the rear wheel.
The motorcycle analogy in this thread doesn't really work.
It is however far more interesting than bicycle cornering.

Yes going in too fast on either is a good way to crash with the possible exception of M Marquez.

https://youtu.be/CuQVKWizmJw

[TobinHatesYou]

Explain further? Being low on the bike doesn't put more weight through the tyres. The process of getting low would first reduce then increase the load on the tyres very briefly, then you're back to where you started in terms of total weight.

Sorry, yes, I meant getting the CoM lower, closer to the tire patch.

[spokenwords]

All I know is I used my knee to dive into a corner and it just seemed to happen automatically, and it worked.