Some of this is funny, other parts that seem funny are spot on serious.
Step 1: put on socks, slide across a hardwood floor until you can slide 10ft+ repeatedly and laugh the whole time
Step 2: get a skateboard and ride it, the art of balance and how you use your body to influence it is important
Step 3: breath... relax... learn to only react to what you really need to react to. If you need an extreme example, get 3 friends... give 2 of them pool noodles, give the other a baseball bat and tell them to hit you
Step 4: ride the skateboard again and notice the differences in the reactions you DIDN'T have. Repeat the steps if you're still reacting to EVERYTHING or don't understand what I mean (take control by doing nothing )
Step 5: ride in the dirt as much as you can, then over the winter... ride on snow and ice for extra fun
Step 6: do this until you can drift around corners on dirt, mud, snow or ice while laughing 100% of the time
Now you're ready to explore the upper limits of traction on a bike on pavement. lol!!!
Honestly, you only have 2 types of feedback that you get from the bike. It will be either positive or negative and you only want enough feedback (either kind) that you can work with. Too much is just as bad as too little.
So getting back to finding the traction limit... the answer is, there is no answer that will fit 100% of all scenarios. If there was, we all would be traction masters. Instead, focus on assisting the bike delivering positive feedback to the rider. Which is basically why some riders can go faster than others in less than optimal traction conditions, the same thing also holds true when the conditions are perfect for optimal traction. At any time it doesn't feel confidence inspiring, stop right there and figure out why you're not getting that positive feedback of stability. Sometimes, it's the bike setup, sometimes it's the tires, sometimes it's the track, other times the weather, maybe it's simply just the rider having an off day or running into their skill limit. The bottom line is, even if the bike is far from the limit of traction, the risk of crashing goes way up when the bike or rider starts complaining in some way. Many times the rider starts to address these problems via unneeded or improper inputs or changing settings thus reducing the available traction that they ALREADY have. :\
I will use myself as an example, I am not exactly slow, but nowhere near the fastest.. but my bike rarely slides or loses traction even with some of my fastest paces. Those who have attended the track with me can attest to how LITTLE I reference the available grip, yet ride just as fast or faster than the majority of riders on the course. I credit this to prevention, NOT acceptance and anyone can follow that pretty easily imho. Throughout my riding, I have learned that I prefer a stable front end. The rear of the bike can move around as needed but the front must stay nearly 100% stable for me to have full confidence, other riders are the exact opposite. In that respect, I am “needy” of the front and less needy of the rear. To isolate this specific area of my riding, I stopped changing things with the bike and stuck with a pretty decent setup and one brand and model of tires. Since the bike didn’t change, I was free to work on me “feeling” available traction and grip at different paces, lean angles and track conditions. It wasn’t what I learned about grip that was profound, what was amazing… is what I learned about myself. Going further, I learned that it wasn’t even about me in the first place, it was about satisfying the minimal needs of the bike.
Find your frames of traction reference...
Now as a learning rider, some of the major traction indicators are missing or greatly exaggerated. Lean feels greater for beginners, than experience riders, lack of traction feels greater than experienced riders, Others feel little slides greater than more experienced riders. Why? Because those more experienced have more frames of reference and more experience with those frames of reference.
The big ones... (frames of reference)
Bars - you can feel what the front is doing
Seat - you can feel what the chassis is doing
Pegs - you can feel what the swingarm/rear is doing via the balls of your feet and even heels on the swingarm on some bikes, if you have tidy feet
Knee - you know where the tarmac is because it just touched your knee
Head - you know how much the bike is leaned over (head bone is connected to your knee bone lol)
Now, as a learning rider... how much workable input are you really getting from the big frames of reference? And I am not even including the small ones. ijs... And what if one or more of the big ones are missing or not working right? What if your not going fast enough to drag knee yet? Now your missing a huge input on lean angle vs where the ground is. What if your are unhappy with your rearsets or not riding on the balls of your feet? See what I mean?
Since riders don't normally attend a school every track day, it's safe to assume that at some point the next time a rider hits the track, they will be on their own. Some riders might enlist the help of CR's/coaches but they may not (you should, that is what we are here for). So many track orgs that I have been exposed to, error on the safe side, and present the following; "All you have to do is practice skills and the speed will come to you". Just like almost everyone says, "don't try to drag knee, get your skill up and it will happen all by itself."
Since we are not bound by any rules of writing a short and complete article we can break the RAW fundamentals of traction down into the big 6 factors to build a picture of traction from the ground up (literally).
The short list of traction from the ground -> up
1. The surface you're riding on - The different mixes of the tarmac. The mix is regional!!! JenningsGP grips differently than Mid-Ohio as Nelson grips differently than Palmer and even different that streets or Laguna. The raw materials that the track is made of different raw materials and different amounts of those materials. They can feel different to the rider and what you get away with at one track, may put you in the dirt at another.
2. The type of tire you're riding on - Different tires are harder, softer, size, compound, recommended pressures, bla, bla, bla, bla. They can feel different to the rider. For me, the Michelins carcass starts to flex a bit closer to the traction limit of the tire. Some say they don't give as much warning as the Dunlops. If we were to dumb it down for example's sake, say the following tires will have a 100% traction failure and 100mph. The dunlops will start complaining at 90mph vs 95mph on the Michelins. Some riders want the larger window of warning, others are fine with a smaller window.
3. Suspension - These adjustable bits can increase feel (harder settings) or take away feel (softer settings) as well as feedback to the rider and have a huge effect on traction and how much you feel vs what the shocks eat up/nulls out.
4. Grips, seat, pegs and any other point where the hard parts of the bike comes into contact with the soft parts of the rider - Race seats are thinner. Why? We don't have super fat grips on our clip ons. Why? We don't use rubberized rearsets. Why? How does the tank feel on your chest in a full tuck if you have a chest protector vs not? These can feel different to the rider.
5. Gear - Have padded shorts under your suit, or maybe really thick gloves? One of the selling points of gloves is increased feel in the palm and sometimes fingers. Do you prefer thicker or thinner soles on your boots? These can feel different to the rider.
6. The rider's tolerance/ability/skills - Get warmed up as a rider and prevent some SR's before they become distractions or action items.
On the first lap or two, I use my legs to support some of my body weight on the bike to prevent some of the little bumps, skips and slides from making it to my head as sr's.
I guess I will also let this little racing secret out of the bag... I call it the "spread effect" in short, but it's really, really, really getting a good lock on the bike. When you stand straight up, you support your weight 50/50 with each leg. Do you support your weight evenly on the bike? What part of the bike supports the majority of your weight? It's not the bars for sure... so I like to spread my weight evenly over the seat, pegs, knee on tank, chest on tank when tucked or arm on the tank when hanging off. To start off, this means the suspension does not have to compensate for me as the rider in general. This also lets me move around more fluidly on the bike, especially sliding across the seat with ease. Feel of traction wise, it ensures I don't get too much "localized feedback" and a better definition of what the whole bike's traction level is. Basically the muscles in bumm, legs/knee, chest, and whichever arm is on the tank act as buffers or noise gates to my head. Sometimes I use use them to dull the feeling of lack of traction or increase the feeling of traction by paying more attention to those contact points. Most importantly, it allows me to really isolate my throttle control to move weight around. After all, your main goal while riding is to "keep the bike stable". If you repeat the throttle control rule 1000 times, this one should be repeated 999 times. This is how I define my instinct while riding.
All of these things combine to paint a beautiful picture of traction or lack of it, that is then perceived to the rider. Each of us feel it differently and is just as much an art form, as it is a skill in all to itself. The better your skill, the more traction you can detect and... even sometimes get away with going beyond it a little bit.
So far.... I haven't seen anything, anywhere that is a better explanation of a very complex subject.