How Do You Read Traction?

[4erramses]

I am interested how you guys are sensing/reading Traction? Are there some specific practices you do to check traction?

[rchase]

In the dry I'm usually pretty far from limits of traction unless I make a mistake. Mostly due to my penchant for the stickiest tires I can get my hands on and warming them up to 180 degrees before I even go out. In the wet though it's a different story.

 

I use feel rather than visual factors to judge traction. You can feel the little slides and squirms under power and that gives you a good idea of the grip level. The cool thing about feel is you can sample the traction limit each lap. During a rain storm the grip changes. At first the track gets pretty slick. The rain changes the track surface by washing away things embedded in it. It could improve or it could get worse depending on the surface. Rain can also cool the track and can affect traction that way too.

 

I find that some visual information can be misleading There's a track that's a great example of this. Talledega GP in Alabama. In the only right hand turn on the track it's riddled with patched pavement that looks like it's trouble. It looks bad but there's tons of grip there.

 

Some visual stuff is pretty useful. Is the track damp in sections? Are there tar snakes? Debris or sand?

 

Another thing to think about is the ambient temp of the air and the track surface. It could be a nice warm sunny day but if the night before was super cold your first sessions are essentially on a cold track. It might as well still be the night time temperature outside. I'll often feel the pavement in the pit area to get a sense for its temperature. Is the sun heating it up? On the flip side of that did it burn your hand? Overheated tires can be as troublesome as cold ones.

 

Hope this is helpful.

[4erramses]

Thx rchase, make sense. I am more interested in the feelings you get while riding and testing traction.

 

How you read it? Are there some practices to test it in a safe way?

 

How can I educate my feelings on traction in a safe way?

[khp]

I guess I should add

to this:

 

If you're in doubt that damp patches are more slippery than 'dry' track, go see the Argentinian MotoGP race. Several racers (in both Moto2 & MotoGP) went down in the final stages of the races, because they missed the line by 2' and ran the front/rear tyre over a damp patch.

[YellowDuck]

If it is a clean hot track and I am going out on hot tires I don't even think about it. When traction is suspect (e.g., very cold track in the morning) all I do is work up gradually to my normal cornering speeds and braking effort. It's usually the front wheel that gives it away, with a little slide on braking or a loose feel while cornering. When it is REALLY cold (like, first track day of the year around here, maybe early May, when the track in the morning is cold to the touch even in full sunlight) it is more about being wary of the *loss* of traction as the tires cool over the course of the session. Coming right off the warmers I might get only 3 or 4 laps before spooky stuff starts to happen to the front, or maybe the rear spins up a bit on corner exit. It's pretty easy to sense - not mysterious at all.

[rchase]

If it is a clean hot track and I am going out on hot tires I don't even think about it. When traction is suspect (e.g., very cold track in the morning) all I do is work up gradually to my normal cornering speeds and braking effort. It's usually the front wheel that gives it away, with a little slide on braking or a loose feel while cornering. When it is REALLY cold (like, first track day of the year around here, maybe early May, when the track in the morning is cold to the touch even in full sunlight) it is more about being wary of the *loss* of traction as the tires cool over the course of the session. Coming right off the warmers I might get only 3 or 4 laps before spooky stuff starts to happen to the front, or maybe the rear spins up a bit on corner exit. It's pretty easy to sense - not mysterious at all.

 

 

A very very good write up. Especially the part about the warmers. On a cold track even with warmers your tires cool at an alarming rate. You have the track itself pulling heat out of the tires but if there's a long straight you get wind chill on a cool day.

 

Roebling Road is a good example of being cautious about traction on a cold day. There are only two left hand turns on the entire track. When tires start to cool it starts to become a problem. Riders come blasting down the straight at 170mph (with the wind blast cooling off their tires) and then go into a right hand turn. The grip they get on the right side gives them a false confidence for the upcoming left hand turn where their tires are sometimes too cold to maintain grip. The result is that the front end lets go instantly and they crash.

[rchase]

Thx rchase, make sense. I am more interested in the feelings you get while riding and testing traction.

 

How you read it? Are there some practices to test it in a safe way?

 

How can I educate my feelings on traction in a safe way?

 

Yellowduck pretty much said exactly what I would have. Check out his response.

 

For many years I had some irrational fears when it comes to traction. Sometimes it comes back when I'm feeling uneasy. It took a 2up ride to educate me on how much traction there is available out there. Way more than I could have ever imagined.

 

It's also important to keep in mind that traction issues are progressive in nature. If you slowly increase your pace traction issues will start to present themselves in very harmless ways to let you know you are approaching the limits. A little slide here, a wiggle there all quite manageable if you stay calm. If you step WAY over the limit right away that's when the big problems come. If you are sensible though you aren't going to be surprised by a sudden lack of grip unless you are riding on cold tires. Tire warmers help a lot with this and for myself are a huge help to remove the doubt that I often have with grip.

 

In racing my guess is its not very different. Use your practice sessions to slowly and progressively test the limits of traction until you know where you are at for the race. Get out there and ride at that limit or slightly below it and then also slowly ramp up the speed until you see the signs of traction issues. The most talented on the track know exactly where the limit is and often step over it when it suits them. Either to pass or to help steer the bike by using intentional rear end slides.

[Hotfoot]

On a cold day on the first session out (when not using warmers) I notice the tires themselves feel stiff and respond differently than normal; on the Dunlop slicks they tend to be a little resistant to turning and seem to want to stand the bike back up out of a lean, I think they are just stiff with cold so the contact patch doesn't flatten to the pavement like normal. That is the most obvious indicator to me that the tire is definitely cold and I need to be cautious. Beyond that, I just try to use very good technique (good throttle control, good body position, loose on the bars, etc.) and gradually increase my lean angle, and braking and acceleration. That way, as Robert says below, you feel SMALL wiggles or slips that warn you, he says it well:

 

It's also important to keep in mind that traction issues are progressive in nature. If you slowly increase your pace traction issues will start to present themselves in very harmless ways to let you know you are approaching the limits. A little slide here, a wiggle there all quite manageable if you stay calm. If you step WAY over the limit right away that's when the big problems come.

 

If worry about traction is a distraction for you, sometimes you can get more comfortable with it by intentionally riding in some low-traction situations (safely and carefully) to get more familiar with slides and warning signs. A little dirt bike in mud or loose dirt a good way to practice, for example; it's not exactly the same but some of the ideas translate, like feeling and recovering from little front end slips, or feeling the back end squirm when you are on the edge of traction. Riding minis on a go kart track is great too - they handle more like a sport bike but you aren't going so fast so it's less intimidating. There is also the Slide bike at the school, there are some qualifications to ride it but the purpose of it is to experience losing rear wheel traction and learn how to recover without a highside.

[YellowDuck]

This is a bit of a tangent from this thread (sorry) but I just wanted to add that, when I first started track riding, my biggest limitation was an inability to trust in the amount of traction available. There is a long thread about this called "Learning to Trust the Tires" or something like that. I eventually got over it by adopting more of a quick turn steering approach where I screwed up my courage and just chucked it over hard, as opposing to sort of easing into a turn.

 

I am way past that now on dry, warm pavement - my corner speeds aren't really limited by my faith in the tires, and in a race situation even when I am turning relatively slowly while trail braking I can still eventually get it over to my normal full lean angle.

 

And yet, in low traction situations I am still a chicken. Meaning I can still be super cautious to the point where I am not using all of the traction available, or even close to it. Best example last season was the final inter-series round where we had had rain and there were damp patches all over the place and, right at a corner exit, a little tiny "river" running right across the track. I was on slicks (it was too dry for rains) and could never bring myself to ride through that water at anything more than a snail's pace, even though I saw my competitors doing it much more quickly. Just couldn't get my head around it. I got lapped that race....

 

Which is all just a long-winded way of saying, psychology weighs into all of this very heavily, at least for me.

[rchase]

I think you are 100% right about the psychology. In a lot of ways suspension technology makes riders faster by psychology as well. Because riders don't get the input that scares them they go faster.

 

I have a weird psychological problem as well. I love the wet. The reason for this is I can constantly sample how much grip I have and I know exactly where I stand. In the dry you have to add a LOT of speed in order to start feeling the limits of the traction. That speed makes a mistake way more costly. I have gotten around this by reassuring myself that there's an ocean of grip. I probably should take Hotfoot's suggestion and go get some cheap tires and do some skating around in the dry.

[drioannis]

All these are good points but for "feeling-reading" the traction there is only one word...EXPERIENCE. "Reading" the traction is the most difficult thing to to in the track. This is what makes the difference in racing.

[Hotfoot]

This is a bit of a tangent from this thread (sorry) but I just wanted to add that, when I first started track riding, my biggest limitation was an inability to trust in the amount of traction available. I eventually got over it by adopting more of a quick turn steering approach where I screwed up my courage and just chucked it over hard, as opposing to sort of easing into a turn.

 

When I read this comment above, I realized I did that too. Early in my riding I was worried a lot about front end traction. Quick turn helped me with that - I used less lean, I had less time to worry about front end traction, it reduced the necessity or temptation of dragging the brake way into the turn, kept me from overloading the front end with arm tension, and got to max lean much sooner so I was able to get the bike stood up sooner on the exits which helped rear traction too.

[rchase]

Sounds like I'm going to need to work on my quick turn this year. What Hotfoot just mentioned about arm tension just struck a bit of a chord with me.

[Dylan Code]

This is something I wrote a few years ago but never did anything with. Have a look:

 

Placing trust in your tires is fine until they let go unexpectedly. Like a “friendly” cat that suddenly bites and claws your arm, you are always suspicious from that point forward. Sensing what the tires are doing and what sort of grip they are offering seems to be a question of experience and just getting enough miles in the saddle, but some riders come to our school with hundreds of thousands of miles under their belts, still lacking confidence in their ability to sense traction.

 

Available traction can change all the time. What affects it? The list is long; here are just a few factors: tire compound, tire temperature, tire tread depth, tire pressure, surface temperature, road friction, road imperfections, changes in pavement and camber. Suspension, along with the changes one can make, is an art and science all on its own. You also have the biggest variable of all--the rider with his use of the controls along with his body position in relation to the bike.

 

Trying to weigh these factors against each other during a ride is impossible so it’s more a question of feel versus mentally tracking an infinite number of variables.

 

The clue to sensing traction lies in the fact that tires are always slipping when you corner. Car buffs know the subject of “slip angle” well. Slip angle refers to the difference between where the tires are pointed through a turn and your actual heading. For example, a driver turns his front wheels into a turn 13 degrees. If the car carved an exact 13 degree arc there would be zero slip angle. However what we actually see is the wheels turned in 13 degrees, but the car carving let’s say an 11 degree arc. The slip angle in this example would be 2 degrees. Motorcycles also have slip angle. My main point in bringing this up is simply to point out that the tires are always slipping a little when cornering and how much they are slipping gives us a clue on traction before the tires completely let go.

 

Where it gets very different for a motorcyclist is when we consider the factor of lean angle against speed. We as riders have grown accustomed to expect a certain arc from the motorcycle when leaned in at a certain speed. When we get a departure from what the rider knows to expect, they should be suspicious of traction. Example: a rider leans their bike into a turn and finds it running slightly wider than what they would expect. The rider also notices that the bars have slightly less tension in them--they feel “light” in the hands. This would be a dead giveaway that the slip angle in that instance is greater than usual. Merrily leaning the bike over more could result in a total loss of traction. Incidentally, this is another reason we don’t want a death grip on the bars--it obscures one’s sense of traction by hiding the tension or lack thereof in the bars, another clue as to level of traction.

 

If you know what to look for, your prediction of traction can improve. But again you have to know what to look for. Just like that cat that unexpectedly scratched your arm. You may not have noticed its tail whipping back and forth in a jerky, rhythmic pattern just before it pounced.

 

This is perhaps an oversimplified view of a deeply technical subject but we have to start somewhere if we want improvement in our cornering. Again and as always, the track is the best place to work on your sense of traction and its other components such as speed, lean, line and surface.

[Willsportbike]

.... just getting enough miles in the saddle, but some riders come to our school with hundreds of thousands of miles under their belts, still lacking confidence in their ability to sense traction.

 

 

 

Well said...and yes this seems to apply to me and I'm sure other riders. Still struggling and I hope to build on the confidence while training in Aug.

[khp]

Trying to weigh these factors against each other during a ride is impossible so it’s more a question of feel versus mentally tracking an infinite number of variables.

 

The clue to sensing traction lies in the fact that tires are always slipping when you corner.

 

[snip]

 

The rider also notices that the bars have slightly less tension in them--they feel “light” in the hands. This would be a dead giveaway that the slip angle in that instance is greater than usual.

 

Great read, Dylan. I think you could evolve this further to a section or chapter in a Twist-3 book.

 

The key take-away for me here is the point that as a rider I cannot - and should not - try to track those infinite number of variables that impact the available traction, but track my feeling of traction; the tire slippage.

 

However, the feeling of a front tire slipping is different from the feeling of a rear tire slipping.

 

The 'light' bars (or even a gentle rocking) is a dead giveaway for a slipping front tire.

For the rear tire, how would you describe the feeling when the tire starts to slip more than usual? - just this Sunday, I doing a trackday with a worn rear and in the last session, the rear felt as it was 'gliding' slightly outwards through a RHS turn (the final turn out on the front straight, so you're feeding the throttle). This was a gentle gliding sensation throughout the first part of the turn (until I could stand up the bike enough to get away from the worn-out part), not a "let go & grip" feeling.

[csmith12]

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.

[Spaghetti]

If the tires are always slipping when we corner, then isn't the real question when is the bike falling out of balance? From moderate pace tires slipping in the corner to the extreme Marquez turns it's a wide range of fine riding. I think the bike falls out of balance when the two wheels have very different grip conditions: the front is gripping well but the rear is not (low side), or the front lost grip but the rear has high grip (high side).