Wet Vs Dry riding

[Jaybird180]

Inspired by the mystery of what to do and not do that is involved in wet riding, I thought I'd start a collaborative list of differences and limitations in riding in the two environments.

To start what we know:

1. You cannot Quick Turn the same
2. You cannot brake as hard
3. You cannot accelerate as hard mid-corner

Anything else?

[Hotfoot]

The overall grip is reduced so anything relying on tire grip has to be backed off considerably - can't lean over as far, can't brake or accelerate as hard, actions must be smooth and gradual so you have time to feel out the traction. And, of course a variable surface (some areas wetter/slicker than others) makes it even more challenging.

I don't know much about this source but here is an article I saw that seems like a decent summary:

https://lifeatlean.com/riding-in-the-wet/

[Lnewqban]

4. Your visor doesn't let you see as well.

5. The rubber of your tires is cooled down and the internal pressure decreases.

6. The feel of your brakes may change, as the temperature of discs and pads is never as high.

7. The feel of your hands and fingers is different under wet leather.

[rchase]

Personally I love riding in the rain.  Less traffic and at the end of the day it's like having your own private track when everyone packs up and leaves early.  When other riders are angry and horrified about the R word I'm thinking "heck yea"!

Some of the things that change in my riding in the rain. 

1.  Braking.  Earlier, lighter, longer.  Stretch out the braking zone and leave yourself a buffer just in case. 

2.  Lean angle.  Less is more.  You stay on the fatter part of the tire and maintain more traction.  Hang WAY off the bike to reduce lean angle.  The more you hang off even at slower speeds keeps you on the more stable part of the tire. 

3. Line.  It's critical to use ALL of the track available to flatten out the corners as much as possible.

4.  Less aggressive quick steer.  I have found that you absolutely still can quick steer in the rain if you stay reasonable with it.  I worried the heck out of a CSS coach when he assigned me the quick steer drill in the rain.  I performed the drill too.  I even got a hug when I came back in one piece. 

5.  Throttle.  You have to be a lot easier on the throttle especially when the bike is leaned over.  On "analog" bikes once the bike is straight up and down you can use the throttle to "sample" traction.  Give it gas and you can feel where the tire wants to spin just a bit. That is the fine line of where the traction ends.  Don't cross the line especially when leaned over. (I would approach this with caution!).  On bikes like the S1000RR in the right mode the bike will protect you for the most part on the gas.  I find that I prefer sport mode or higher in the rain but rain mode is more protective and best to start out with. 

6.  Smooth counts.  Abrupt and sloppy inputs that are ignored because of mega grippy tires are not tolerated at all by the bike in the wet. 

Stuff to watch out for!

1.  Curbing.  It's fine to run over curbing in the dry but in the wet that stuff becomes really slick.  You have WAY less traction than you do in the dry on painted parts. 

2.  Panic.  If you end up overdoing it don't panic!!!!  With less traction the bike is much less willing to be forgiving for sloppy and abrupt inputs.  If you enter a corner too fast just extend your braking past the optimal turn point and use the track you have available.  Bring the bike down to a manageable speed and turn where you can.  Yes you essentially "blow" the corner but by using the track you have you keep it on the pavement. 

3.  Tires.  It's COMPLETELY true what was said about tire temps earlier.  Your tires won't maintain temp.  Not only are you dealing with the slick surface created by a wet track you are doing it essentially on cold tires.  I set a cold pressure and leave it there.  You can even experiment a bit with dropping the pressure but I'm not really sure it helps much and can potentially make the bike feel a bit mushy and imprecise if you overdo it.  You still won't get a lot of heat in the tires. 

4.  Your physical condition.  Riding in the rain seems easier but you do still get tired.  Since you aren't sweating like crazy the fatigue sneaks up on you.  I rode every single session of a wet track day only to figure out during the last session that I was a lot more fatigued than I realized.  This fatigue can be both mental and physical.  Stay sharp!

[rchase]

A couple of other things to be cautious about. 

1.  Puddles.  Not only because of the hydroplaning potential.  Hit one at speed and all the water in the puddle nearly instantaneously will soak you and add lots of weight to you. 

2.  Tar snakes and patches.  Not all traction is created equal.  Tar snakes will cause a lot more traction issues when they are wet.  Some patched areas have more or less traction than the main part of the track. 

3.  Visibility.  Visor fogging (easily fixed), Mist from other bikes, fog and rain on your visor can reduce visibility.  Use a clear shield at all times to avoid this and preferably a clear windshield on your bike to maximize visibility.  The straights are a gigantic wind powered windshield wiper for your helmet if you stick your head up in the air stream and move it from side to side. 

4.  Slippery when wet.  Controls, pegs, tanks and other parts of the bike are not as easy to hold onto when your bike is wet.  Be aware. 

 

[Jaybird180]

52 minutes ago, rchase said:

Personally I love riding in the rain.  Less traffic and at the end of the day it's like having your own private track when everyone packs up and leaves early.  When other riders are angry and horrified about the R word I'm thinking "heck yea"!

Some of the things that change in my riding in the rain. 

.....

3. Line.  It's critical to use ALL of the track available to flatten out the corners as much as possible.

 

Great list and write-up! Wrote any good books lately? (LoL)

I'm very much interested in asking about #3 above. I recently reviewed the chapters on steering in TOTW2 and had not before paid as much attention to one of the drawings comparing lines. In one drawing the rider made a smooth arc through the corner but in the other, the rider made a sharp hook at the steering input and it seemed as if Keith was advocating the hook. I'd think that a rain rider might also prefer a hook as they are on the side of the tire less. If this is the case, why use the far side of the track for entry since it will put you in the same place anyhow with "midcorner" being a geometric line (instead of a curve)?

[rchase]

I'll be honest.  I'm no expert.  I'm just sharing my personal experience. Trust the experts rather than a random person like myself on the internet. 

Personally i use a longer line in the rain.  It allows me to be more smooth and less abrupt with my control inputs.  All of the lines and riding tricks like the hook turn and quick steer still work in a lower traction situation you just have to "dial it back" a bit and not be aggressive with them.  Ultimately you need to ride both lines and see which one is faster for you and which one gives you the most confidence.  The key to riding in the rain is trust and confidence.  I still remember the apprehension and amazement that I had when I eventually developed the courage to start pitching my ancient little Yamaha into wet corners at speeds beyond my comfort threshold.  I fully expected the possibility of crashing. 

I personally have a lot of confidence about traction in the rain because you easily get to that limit at lower speeds and know exactly where you stand. Intentionally spinning up the rear when it's safe (straight up and down) is a great way to sample the grip you have.  In the dry on super sticky race slicks you have to get to really high speeds before you can sample traction and it's much more critical then.  I ultimately prefer it that way (more grip is more resources to work with) but it's a lot more of a challenge to find the limit.  I have been tempted many times to put low grade street tires on my bike at the track to be able to feel traction but have never been able to bring myself to giving up the amazing feel I get from the Pirelli Slicks that I love so much.

Traction ultimately is the main tool that we use in all conditions.  Understanding what you have to work with and how your actions affect it help greatly with accomplishing your goals.

On the writing thing. I have written a few articles, manuals and other documents about riding (ironically including a race manual even though I have never stepped foot on an active grid other than to check tire pressures as pit crew).  Most of the stuff I write is to support a local track day org that I'm involved with.  Very few things have been published other than an article for a magazine.  While I would write more there's lots of people out there who know more and have way more experience than I do. 

[Jaybird180]

I'm planning to ride dirtbikes with my son today so I can sample some of the reduced traction you speak about. Ciao!

(please keep the thread going)

[Lnewqban]

On 10/19/2017 at 10:47 AM, Jaybird180 said:

......... I recently reviewed the chapters on steering in TOTW2 and had not before paid as much attention to one of the drawings comparing lines. In one drawing the rider made a smooth arc through the corner but in the other, the rider made a sharp hook at the steering input and it seemed as if Keith was advocating the hook. I'd think that a rain rider might also prefer a hook as they are on the side of the tire less. If this is the case, why use the far side of the track for entry since it will put you in the same place anyhow with "midcorner" being a geometric line (instead of a curve)?

In that hook is the main advantage of the quick-flick technique: a rider can achieve a few degrees of change of direction (horizontal) during the relatively safe transition from vertical to full lean angle.  That lean angle will be less dramatic than the resulting lean angle (and cornering forces) of a lazy entering steering.

In every turn, we must change the direction of the motorcycle.  There is always an angle between in and out directions (45, 90, 120, 180, etc. horizontal degrees).  The racer who can "rotate the nose" of the bike sweeping the full horizontal angle in less time, without crashing, has an advantage.

An important limit to that rapid change of direction is available traction.  According to Sir Issac Newton, any body in movement will follow a straight line, unless forced to change direction.  Steering and available traction are all we have to force the bike to turn.  The faster the turn, the stronger the cornering force (proportionally to the square of forward velocity).  The tighter the turn,  the stronger the contact patches need to grip the asphalt (inversely proportional to the radius of the circle described by the bike at each moment).

The angle of lean at each moment is a very accurate reference for us to learn how intense is the cornering force that is trying to break that grip of the contact patches and to help the bike resume the straight trajectory (which is the natural thing, rather than turning).

Since the quick-flick gains some bonus degrees of horizontal rotation for us and reduces the magnitude of the final lean angle some degrees (meaning less cornering forces), we can increase the speed around the corner in order to use that little reserve of traction.

The quick steering uses the abundant traction of the vertical front tire and simultaneously rotates and flicks the bike certain amount of degrees.  Regarding the line or trajectory, it means that we are transitioning from a straight line into a curve of constant radius as quickly as possible.  A lazy entering steering is what we normally do in a car, because it takes some time to rotate the front wheels.  What our car describes is closer to a parabola than to a semi-circle, it looks and feels like a decreasing radius turn.  Please, see:

https://en.m.wikipedia.org/wiki/Euler_spiral#Track_transition_curve

https://en.m.wikipedia.org/wiki/Racing_line

The lazy entering steering produces the same effect: less lean angle at the beginning, which trades off for a extreme lean angle (and cornering forces) around the apex (or tip of the parabola) where the radius of turn becomes very small.  That extreme lean angle becomes your bottleneck, regarding speed and traction, even if you trail-brake all the way until there.  Sooner or later you must rotate the nose of the bike around, quick-flick allows you to do it sooner (and safer) than later.

Quick-flick goes very well with the late apex approach and allows a line that straightens the geometric curve very much.  Using more width of the track when/where possible can increase your speed and improve your line of sight. The direction of the following turn is important when choosing a wide or narrow line out. 

Remember, on dry or wet pavement, the best and safest trajectory is that one that allows you to use the throttle golden rule.  More discussion about that "hook" and quick-flick in wet conditions can be found here:

http://forums.superbikeschool.com/topic/4101-can-quick-turn-be-overdone/

[DucPati]

On 10/20/2017 at 12:40 AM, rchase said:

A couple of other things to be cautious about. 

1.  Puddles.  Not only because of the hydroplaning potential. 

When I did lvl1, it rained at the end of the day, for the last session. Lots of people stayed in the pits, but like you I actually like riding in the rain. I was on my Multistrada, traction control still enabled but I have it one level more intrusive than the track setting (the manual says the track setting won't save you). Here's what happened coming onto the start/finish straight (and yes I intentionally provoked it, I often do in the rain ):

 

https://www.youtube.com/watch?v=ijEUD_QcjvY

It was red flagged that lap due to the water not draining off the track. I was using Metzeler K3's which are in the wet. Normally run M7RR which are great in the wet.

[DucPati]

On 10/20/2017 at 2:21 AM, Jaybird180 said:

I'm planning to ride dirtbikes with my son today so I can sample some of the reduced traction you speak about. Ciao!

I hope you know about this game called "Roost your mates"! It's compulsory when riding in the dirt and helps you get comfortable spinning the rear

[rchase]

On 10/20/2017 at 10:15 PM, DucPati said:

When I did lvl1, it rained at the end of the day, for the last session. Lots of people stayed in the pits, but like you I actually like riding in the rain. I was on my Multistrada, traction control still enabled but I have it one level more intrusive than the track setting (the manual says the track setting won't save you). Here's what happened coming onto the start/finish straight (and yes I intentionally provoked it, I often do in the rain ):

 

https://www.youtube.com/watch?v=ijEUD_QcjvY

It was red flagged that lap due to the water not draining off the track. I was using Metzeler K3's which are in the wet. Normally run M7RR which are great in the wet.

Fun video.  Had you waited a fraction of a second to get the bike completely upright that video would have been less interesting.  The "yaw" that you got from the rear of the bike was likely because you were still leaned over a wee bit.  When I'm intentionally "provoking" the rear tire to see where it breaks I usually wait until I'm fully upright.  It gets me the info I want with less thrills involved.