stuman

No it is not true.

I always do clutchless upshifts no matter what I'm riding. Downshifts: On the street I do clutchless downshifts On the dirt I do mostly clutchless downshifts, although i do use the clutch in some corners Supermoto - On a supermoto track I use the clutch for down shifts. However, I don't blip the throttle, I just grab the clutch drop a few gears and let the clutch out slow Roadracing - a mix of clutched and clutchless downshifts, I always blip the throttle either way

Doug Chandler. Not only is he a really nice guy, but I really admire his riding style. He is so smoooth it's just silly. They don't call him Doctor Smooth for nothing. I believe he has a riding school these days here in CA.

One of our instructors (Misti) wrote a great article on the subject of tank slappers. I hope she doesn't mind my posting this... Ashen and trembling I maneuvered my California Superbike School Kawasaki 636 off the track and into the hot pits, pulling up next to course control and a few of the other coaches. They took one look at me, my white face and shaky hands and asked “what happened?” “Tank-slapper,” I replied sullenly and they all laughed, “welcome to the club!” I was at Reno Fernley Raceway, coaching with the California Superbike School when I experienced the scariest moment of my riding history that didn’t end up in a crash. I was working with a very fast student, an unassuming guy that I never thought was going to be as fast as he was, but he was blazing, and getting faster and faster each session which meant I had to work! The layout at Reno Fernley raceway (it has since been added to and modified) was fun and fast with a smooth front section that flowed really nicely. The back section however, was extremely bumpy in a kind of wavy and rippled way, and all morning I had been a little nervous and tentative going through it. It happened later on in the afternoon, I was sitting parked off of the track near the front straightaway when my fast guy student screamed past. I pulled onto the track quickly and raced after him, closing the gap considerably in the first few turns. When he pulled onto the back straight however, he was still about 10 bike lengths ahead of me and I needed to close the gap further if I was going to observe him ride. As coaches we usually follow our students for a lap or two and then get in front and lead them for a lap or two. I twisted the throttle harder to close in and everything was going along fine until I hit one of the bumps so hard it bounced me right out of the seat. When I came down the bike jerked and bounced and the bars started to shake from side to side, tossing me back and forth with it. I thought I was going down and for an instant, out of sheer panic I clung to the bars and tried to make it stop. Big mistake, the bars started shaking more violently, I was bounced higher and harder in the seat and as much as I tried to hold on to the handlebars I couldn’t. They were literally ripped right from my hands and started slapping into the tank going from lock to lock. I prepared to eject. I was quite literally about to jump off the bike when an amazing thing happened, the bike started calming down and straightening itself up. I was so excited, and eager to regain control of my machine that I grabbed at the bars again and the instant I clamped down on them they started shaking wildly again. This time I smartened up to what was happening and implemented some of the very basic things that I teach every day at the California Superbike School about rider input. Basically, as Keith Code says in his book Twist of the Wrist II, “riders create more problems than motorcycles are designed to handle.” What he means by that is that the more you interfere with what the bike is trying to do on its own, by holding on too tight, by trying to muscle the bike around, by squirming and wiggling and messing about, the more difficult it is to have a stable bike. Yes, all these thoughts did zoom through my head as I was flailing around on my bike like a stunned chicken, leaving foot long skid marks trailing behind me. I squeezed the tank with my knees, raised my butt a little bit off the seat to help soak up bumps with my legs (like a jockey riding a horse) loosened my grip, made my arms like wet noodles and tried to relax while rolling on the throttle. After another series of wild jerks the bike calmed down and I had regained control. Whew. Then oddly enough I remembered some random comment that a racer had once said to me that at the time had made no sense at all. “If you ever have a tank slapper, remember to pump up the brakes afterwards because it can cause them to not work at all.” I reached for the brakes as I approached the left hand corner at a high rate of speed and low and behold, no brakes! I pumped wildly, got the bike slowed down enough to make the turn, looked up the track to see my speedy student disappearing in the distance, rode straight for pit exit, and into an awaiting group of shark like coaches who thought my whole experience was funny. Funny? So what exactly is a tank slapper anyway? Let’s break it down. A tank slapper is a rapid, high intensity and unwanted motion of the handlebars back and forth. Literally it is the slapping of the bars from side to side that can get violent enough to actually hit the tank of the motorcycle, hence the name “tankslapper.” The bad news is that they are scary as hell and can cause some pretty nasty crashes. The good news is that there are some very effective techniques you can use to handle them. What causes tank slappers? The suspension system on a motorcycle is designed to make the ride more comfortable for the rider and primarily to keep the tires in good contact with the road surface which can include bumps, cracks, pot holes and all manner of imperfections. This system must work while the motorcycle is straight up and down and also during turning when the bike is leaned over, sometimes at very extreme lean angles. In his book, A Twist of the Wrist II, Keith Code explains, “the process of head shake (which can be the beginnings of a tank slapper) begins when the tire hits a ripple and, along with the suspension, compresses. This throws the wheel slightly off-center. When the suspension and tire release, the wheel is light and flicks back toward a centered position, but again, slightly off-center. Still off-center when it loads again from the next ripple; again it is flicked past its centered position. The cycle of flicking back and forth repeats as the front-end seeks to stabilize through this automatic and necessary self- correcting process. Any bike will do it, and what most riders fail to realize is that this shake is a necessary part of the bike’s suspension system.” The little wiggle in the front of the bike is how the motorcycle self corrects and gets itself back on track. Ever see a motorcycle race where something, either a tank slapper or a big slide causes the rider to either be ejected from, or fall off the bike? As soon as the rider is no longer on the bike it wiggles a bit, straightens out, keeps on going perfectly straight until it runs out of momentum and falls over. This is a classic example of how a bike, if left to its own devices will sort itself out. Code mentions that, “based on the amount of wiggling, squirming and overuse of controls most riders exhibit, the bike would, if it could, surely ask them to leave. Riders create instability on their own mounts.” Head shake can be caused by hitting a bump or a ripple in the pavement or it can occur when accelerating hard out of a corner. Hard acceleration can cause the front end to get light or even wheelie which means that the tire is no longer following the road very well, and when it touches back down it can skip or bounce or be off-center, starting off the headshake. Code explains that, “the good news is that if your bike is basically tight (steering head bearings not excessively worn, forks and shock not sticking etc.) the head-shake stays up front and does not transfer to the rest of the bike.” Eventually, the oscillation will die out on its own, unless we interfere. How Riders make the situation worse: Our normal reactions when the handlebars start to slightly shake are to stiffen up on the bars. Keith Code calls this our “survival reactions,” noting that we do not usually choose to get stiff and tight on the bars, our bodies just do it. When we stiffen up the head shake is transferred through our bodies to the whole bike and that is when the shaking can get more violent. Code says that “too tight on the bars is the most common source of motorcycle handling problems.” How to Prevent a Tank Slapper: Knowing that gripping the bars too tight is what transfers head shake through the bike and makes it feel like a ferocious tiger ripping a piece of meat into shreds, we can work to prevent a tank slapper from ever occurring by maintaining a relaxed position on the bike at all times. Practice sitting on your bike with your knees gripping the tank for more stability. Sit back a little further in your seat so that your arms have a nice bend in them with your elbows pointed to the ground and then flap em like you’re doing the funky chicken. That’s relaxed, and from that position you can easily use your legs to lift your weight off the seat a little bit, like a jockey on a horse, so that your butt is not banging down hard on the seat. Think light as a feather, one with the bike, Zen and the art of motorcycle riding…… Installing a steering damper is another way to help prevent tank slappers. A steering damper works to limit the travel and intensity of any head shake that the bike is experiencing by damping or soaking up the excess energy. They are necessary on some of the more modern bikes that have aggressive frame geometry, relatively short wheelbases and powerful engines. Dampers are mounted up front so that there is insufficient leverage to transfer shake through the bike. Keep in mind though that a motorcycle with a damper will still shake if you are tight on the bars, so relax! What to do if you experience a tank slapper: If you do find yourself in the unfortunate situation of experiencing a tank slapper first hand don’t try to muscle the bike or force it to stop as it will only make it worse. Try to relax your grip on the bars, pinch the tank with your knees and lift your butt off the seat a little bit. Also, don’t chop the throttle as that will put more weight onto the front and potentially make the situation worse. Ideally you want to continue to accelerate if possible to get the weight further to the back of the bike, or at least maintain a steady and smooth throttle. Popping a wheelie would eliminate a tank slapper immediately because there would no longer be a front wheel bouncing back and forth in an effort to straighten itself out, but I don’t know too many people that could pull off a stunt like that in the middle of a panic situation. If all else fails, let go. The bike will try to fix itself. Another important thing to remember is that occasionally very violent tank slappers can force the front brake pads and brake pistons away from the rotors, causing the brakes to go soft or even to fade completely. So, once you regain control of the motorcycle, check your front brakes and if they feel soft then pump the lever a few times until the pressure returns. Finding yourself in a situation where the motorcycle you are on is suddenly out of control is no doubt a scary predicament. The more knowledge you are able to arm yourself with, the better equipped you are to handle emergency situations, and the more you are able to practice certain techniques (such as being nice and relaxed on the bike at all times) the more likely you will be to actually do it when it is absolutely necessary. It’s a pretty cool feeling to be able to consciously decide to do something that makes a bad situation better. Ride Safe, Misti Hurst www.mistihurst.com

Interesting question, I have one of my own... I think it is pretty well understood that there are basically two variables that generate load on the front tire. Braking Cornering The weight on the tires (motorcycle and rider is pretty constant). So we can place load on the front tire by applying the brake. Also load is placed on the front tire when the bike changes direction as well. One of the tenants of trail braking is that you only have 100% of traction available for both variables. Even the best MotoGP tire can be over loaded if you apply too much braking force or too much cornering force or some combination of the two that is greater then the tire can provide, in other words more then 100%. I think basically there are two ways to generate more cornering load, go faster or turn harder. So lets say that under normal circumstances a MotoGP rider uses 70% of the load for braking and 30% for cornering. Wouldn't it stand to reason that if they had very large attachments, they could use 100% of the load for cornering only?

1) If they offer an orientation lap at the beginning of the day, do it. If you can go last and do sort of a modified change lines drill, ride around in the middle slow and take a good look around. 2) first session or two, turn points. Figure out your intended line and choose a good turn point for each corner. Full gears, light brakes. Don't push the pace yet. 3) Third session or so, start to up the pace a little, brake a little harder if you want. Make sure you have enough referance points then work on your "three step", keep your vision out in front of you. 4) Have fun the rest of the day. Maybe practice whatever skill you think you need to improve the most for a session. But really, take a session or three at least just to ride with your buds and rip it up! 5) back it down the last session or two, people tend to make more mistakes when they get tired. Don't push it at the end of the day and if you find yourself not fully concentrating when out on the track pull off. It only takes a momentary lapse of reason (yeah, I did slip a pink floyd reference in there) ......

I like The Streets of Willow for coaching. It has a ton of different corners and you get to practice a lot of different skills. The only think missing is a real high speed change in direction, turn one doesn't really count Vegas infield is a good track for the school too. It is a small track so you get to see each corner a bunch of times in a session and get a lot of practice. It has a good variety of corners as well.

My favorite track in the world, Laguna Seca. I just love that track. It used to be better before the flattened out the crest on the approach to the corkscrew, but it is still a ton of fun for me. Trying to go over turn one pinned on a big bike is a real thrill and the corkscrew... A very close second is Philip Island. It reminds me of a better version of Willow Springs big track. I love the mix of high speed sections with slower corners and change in elevation. That track has everything for sure. These are the tracks like like to ride, not coach. Laguna is one of the toughest tracks to coach at.

Thanks Kevin, I had a ton of fun racing this past weekend. Racing the KX450 against the 650 Twins is pretty entertaining. They have about double the hp that my dirt bike puts out and I had to ride really hard to try to keep up and pass them. Also riding through some of the traffic gets pretty crazy at times, but it all good fun. Here's some on-board footage so you can see what I mean Link to the 650 Twins Race: Link to the Supermoto race:

Best acceleration with most tire will come with about 10% slippage I believe. You can spin to much though and loose drive. The best way I have heard this described is that you want to get the rear tire just churning. Just over the limit of traction so it is churning, but not spinning. There it is clear as mud

There are no seasons in southern california , it is summer pretty much year round. Well really, December is winter and July is summer, pretty much the oposite of down under. In anycase, not much chance of rain at either Willow springs or Vegas. However the do get REALLY hot in summer so if your planning a vacation I would come late or summer early fall.

Nope Mike is blowing me off I did find the PM system though... Top right hand corner, you should see your user name, this is a dropdown menu and the messenger is one of the options...

Looks good Mike Can't find my pm inbox though

Moved this topic to the Cornering Forum as it is the correct place for this type of discussion. Carry on

lwarner brings up a good point. Sometimes you have to time the pass correctly so you don't get balked. Give the guy a little room going in and then cruise past on the exit.

Here's my take. A good student... ... comes with an open mind. ... checks their ego at the door. ... focuses on one thing at a time. You won't fix all your riding issues in one session. Just focus on whatever skill they talked about in the classroom before your ride. ... allows the coach to be the coach and does not try to tell the coach everything they think they are doing wrong. ... pays attention in the classroom and tries that skill on track. ... is willing to try something different and work at it, even if it feels a little awkward at first. ... rides within their limits and is not concerned about how fast they are. ... and most of all tips their coach a large sum at the end of the day

Find better roads. I can have a lot of fun riding really twisty roads even at the posted limits. I don't need to go real fast on the street to enjoy the ride. A road like the tight side of Mt. Palomar is loads of fun even at a sedate pace.

Well, I guess if a quicker change in direction is your goal, and you're willing to sacrifice traction and cornering clearance to reach that, then have at it. I personally don't hang off when riding on the street. However, I do lean my uper body INTO the corner rather then push the bike under me and lean out. Pretty much the way we teach it at the school durring the Steering Drill we do off track durring level 1.

Pushing the bike under you will create excess lean angle, reducing traction and ground clearance. So for anything above parking lot speeds pushing the bike under you to steer is a pretty bad idea. However, it can be useful at slower speeds when you want to create excess lean angle to get the bike to turn a tighter radius, like doing a u-turn in a confined space.

Hey Al, good to see you here. I think it is very important that you understand what you did wrong to cause the problem and it seems you have a good understanding of the factors. In any case, I think once the rear broke loose it continued to slide simply due to momentum. Once the bike broke sideways and began to slide momentum and possibly the additional load place on the tire because of the engine braking cause it to continue to slide. So what should you have done? I'm not sure chopping the the throttle earlier would have helped. Typically in a slide like that once you feel it start to go the best thing you can do is ease out of the throttle just a little. The problem with chopping the throttle at any time is it is going to cause the rear tire to hook up abruptly. If you could have just stayed in the throttle a little you MIGHT have been able to ride out the slide because the rear tire might not have hooked up so abruptly. I think that would have been a tough one to save in any case. When the track is dusty like that I would think the back end would come around pretty quick...

That is a really cool experiment 363Rider! I didn't know the brain worked that way.

Adding lean angle and throttle at the same time = VERY BAD! You're probably right in that you aren't close to the limit of traction yet. When you get closer this could really cost you.

Mostly just so you can get better tires. They don't make good street tires in 19" and 21" so most people switch to 17" or 16.5" so they can get good race tires. I'm sure the 17"s handel way better then 19" or 21"...

I think what the OP is saying is that even if you saw something that close, by the time you reacted (got your fingers to the brake, or even just pulled in in if they were already there) you would have already gone past what you saw. I think the question is how long does it really take you to react. In the OP he states it is 1.2 seconds, does it really take that long to grab the brake?

Very interesting post crash. Now I have to go out and pace off 106 feet to see for myself how far that really is. I think having something that blocked any portion of your vision would make you feel very uncomfortable. The point isn't what you see though, it is where you have your attention. The trick is to ignore the stuff close to the bike and have you attention on what is up ahead. On the track you still want to use your peripheral vision to track your apex, but your attention should probably be on your vanishing point On the street, you can use your peripheral vision to keep track of the center line of the edge of the road while keeping you attention further up ahead.