YellowDuck

(Hopefully this is not another Captain Obvious post...) If you are leaned over right at the edge of the rim, the effective tire diameter would be 17 inches (i.e., the rim diameter). Of course you can't be there because the tire has some sidewall height, plus you need some contact patch beyond the sidewall, so let's say 20 inches. In other words, on a 17-inch rim, leaned right over, the part of the tire you are using has a diameter of about 20 inches. Its diameter determines how quickly it must turn at any given bike speed (actually, its circumference, but circumference is directly proportional to diameter so same thing). Straight up and down the effective tire diameter is a lot bigger. For example, for a 190-section 55-profile tire on a 17-inch rim, the center of the tire is about 4 inches proud of the rim so that is 8 inches more diameter. So, neglecting tire flex, straight up an down you have a 25-inch tire diameter (17+ 8), but leaned over it is only 20 inches. So at any given rate of wheel rotation, straight up and down the wheel travels 25/20 = 1.25 times as far as when you are leaned over. That's a big difference. If you were turning 10,000 rpm when you turned in and didn't change your speed at all as you approached full lean (?!?) you would be turning 12,500 rpm by the time you were at full lean. The bike is covering the same distance in the same time, but because the diameter of the part of the tire in contact with the road is smaller, the wheel has to turn faster to cover that distance. Since the gearing hasn't changed, that means engine speed has to increase to compensate. Hopefully I got the math and geometry right. But that's just theory. In practice it almost never works like this because you are usually turning in on zero throttle, and just the act of turning the bike slows you down considerably. So even though rpms might rise it won't be as extreme as what I just calculated.

WOT means wide open throttle, not redline. So yes you might well have revs left depending on how close to redline you were entering the corner.

Again I will jump in with amateur advice. I don't think there is one answer to your 90-degree 100-kph corner question, because it depends if you are approaching the corner at 110 kph or 200 kph! But yes the basic sequence you describe seems right. Just be sure that you are not adding throttle again until you reach your final (i.e. greatest) lean angle for the turn. Adding throttle + lean = bad juju. Personally most (all?) of my turning is done on fully closed throttle, even if it is closed only for a brief instant. I guess if you have room to be on partial throttle for any distance, then you could have held WOT longer, then closed the throttle before turning. I am sure there are exceptions to this (e.g., quick chicanes) but it seems pretty logical. Also I think it might be easier to get used to the consistent way the bike works while turning on closed throttle. Also, myself, I am probably too much of a spaz to maintain a consistent throttle application (other than zero or WOT) while turning the bike.

This is going to be fun.... From my (amateurish) perspective, the answer is probably most often B, but sometimes A, depending on the corner. It is fairly uncommon to have a corner where you need to go to zero throttle, but still don't need any brakes. Corners that you just need to roll off a bit to set entry speed but then get back on the throttle pretty quickly are way more common. I wonder if some of the corners that you think require zero throttle before entry are actually ones where you could be going deeper, using the brakes for a bit then turning harder. I know I have done the chop, coast, turn thing in a few corners when learning a layout, but as I pushed my times down I got to be WOT longer and then on the brakes before turn in. C - WOT and countersteer....I'm gonna say no to that. As for the steering input, personally I pretty much always steer it hard. There aren't that many corners (slow ones anyway) where quick flick doesn't work for me. The exception would be long, slower corners at the ends of high speed straights, where I tend towards a slightly slower turn in with a lot of trail braking. Okay, now I will shut up and let someone who actually knows something chime in.

Good topic. This is a problem for me as well. Here is butt-cam video of me doing it mostly wrong during a race this year. Honestly I am not sure I could move across the seat very well on my bike without lifting my weight with my feet, because of the shape of the seat and also the tank. The bike is not a modern supersport design. There are aftermarket race seats available however so maybe I should look into that.

....oh, the bike test thing. The only people who worry about those rankings are the ones who don't ride on the track anyway, and so have no perspective on how much difference the rider makes as opposed to the machine. I say, buy whatever sportbike appeals to you for whatever reason. It will be more than good enough. The guy currently leading the points in our local Rookie 600 class is on a CBR F4i...

But aren't we comparing the best riders on what were the best machines of their day, to guys today riding vintage machinery, who may not be the very top tier riders (since all the top tier guys are training and competing on modern machinery)?

Here you go if you want all the details: http://prairiedogracing282.blogspot.ca/2014/08/round-4-ends-with-injury.html

Thanks, I do appreciate it. I have also had great support from the other SOAR racers who have sent me lots of kind messages and reminded me how much they enjoy seeing my strange bike out at the races. Today is a much better day than yesterday - stuff has mostly stopped hurting and I will likely discontinue the pain meds altogether. I have also had two days to process things and so am much less freaked out than I was. The whole experience was pretty gross and traumatic and I must say it haunts me a bit when I lie down in bed at night. That will stop soon too I am sure. Once my head is totally straight my wife and I can discuss the future of my racing career. But I am really inclined to yield to her wishes this time.

The brake lever guard was one of those cheap chinese ones and it got torn out, leaving the end of the clipon bare. I can't help but wonder what would have happened if I had had a proper bar end in there. I had a better setup before - a custom RhinoMoto bar end with a Woodcraft lever guard attached - but that got ruined in a previous crash. Not sure yet about future racing or even track riding. That is a conversation I need to have with my wife. This stuff really upsets her and at a certain point (like coming home with missing body parts) it seems a bit selfish to put her through it.

Somehow it seems funny to me that it is the girl who asks this question. Not sure why. That bike crashes amazingly well. It needs the fairing stay straightened, new clip on brake lever, and throttle tube. Plus some paint on the fairing if I want it to be pretty. But I am not sure when all that will get done because I am at least three weeks away from being able to hold any tools. Maybe longer.

Thanks. No it certainly wasn't Brody. I didn't even know the guy. He did come by the ambulance to apologize though.

Ha! Yes, it was my favorite finger....

My next blog post is not going to be a very cheery one. I was having a good weekend until Sunday morning practice when someone made a very tight pass on me in a slow corner and I grabbed the front brake to avoid hitting his rear tire. Went down hard and unfortunately the handle bar squooshed the middle finger on my right hand. They had to amputate about half the finger. Pretty depressing.

The design of the bike makes such a difference here. Look at the footpeg position in the Rossi photo. It looks like the exhaust pipe or even the bellypan would touch down before his boot. That's nothing like the bikes most of us ride on the track. Rossi's body position is also not that close to my personal ideal, but what works best at 150 mph is not going to be the same as what works best at 65 mph. At a certain point sticking your knee out and getting your torso to the inside is just going to result in your being blown off the bike! Most of us don't really need to factor aerodynamics into our preferred cornering body position....

Well, it sure is a lot of fun but don't underestimate the time and money involved. Buying an ex-race bike that is already fully prepped is definitely the way to go if you want to keep costs down. In my case I couldn't imagine racing any bike other than the Ducati because I just love it that much. It really stands out from the crowd which makes things even more fun because I get to meet so many people who come up to me just to talk about the bike. The first season can be pretty bad cost wise if you don't already have things like tire warmers, generator, trailer, any special safety gear the race org might require, extra required do-dads for the bike (sprocket guard, lever guard, fluid-retaining belly pan, etc.). No single item is that expensive but MAN does it all add up. Another option that many folks do around here is to just rent a race bike for the first few outings. That's a relatively low cost way to get your feet wet. We have an outfit around here called Racer 5 that runs a race school and then will rent fully prepped (with tires) race bikes to their graduates. And yes for sure age plays a role, especially if you want to push yourself at all to try to be competitive. Even at 46 I don't bounce like I used to, but with sufficient attention to personal fitness I think even us old guys can have a go of it. Really half the battle is selecting the correct class to compete in. If you decide to jump in then by all means share your experiences with the forum!

Based on that photo, Tyler nailed it. You need to rotate your hips (and for that matter, your upper body) more into the corner if you want to get your knee down.

There are lots of elements of geometry and technique that determine when and if your knee will touch down. For me it happened in more or less the normal way - I got faster and introduced more lean while maintaining the same body position and eventually started wearing down pucks. But if I had shorter legs, less hip flexibility, bum more on the seat, higher rearsets, more ride height etc etc it would have happened later if at all. Lots of people go fast without dragging their knees, and lots of people go not-so-fast with their knees on the deck nearly every turn. That said, if you don't change anything else about your body position or lines but start dragging your knees, then yes, you are probably getting more corner speed. So, it *can* be a mark of progress. For me, when I am just learning a new track I am not knee down much, but as I figure out the corners I get my knee down in more and more places. For me that is useful information. So, personally I am not neutral on this - knee down = good.

Very interesting. Funny, if you saw that last one (Doohan) at a trackday today you would politely advise the guy to get instruction before he hurt himself!

Amazing what he could do with such an obvious power disadvantage on the long straight.

Ha ha ha. Slasher, check the date on the original post. This isn't a problem for me anymore. I started racing this season and am happily cornering the bike to the edge of the tires (and sometimes a little beyond ). Good advice though! I think the idea of using a lower gear to increase stability might have worked....you know, two years ago.... Actually, I am a bit surprised it was only two years ago that I was still searching for the courage to find more lean angle. Seems like a decade.

You know, I don't think the camera is on quite straight which makes the lean angle look like more than it is, but still he (she?) has the bike WAYYY heeled over when the touch down occurs, yet body position is just a normal street riding "Ianetsch pace" kind of setup. If you are going to carry that kind of corner speed I think you need to get off the bike a bit more, or at least get your upper body weight more to the inside. And maybe get the knee out so you know where you are. Weird stuff happens when you try to go fast without sufficiently aggressive body position. Last race round I got on the endurance bike and for whatever reason in one of the early corners I just didn't adopt my normal cornering position. I really wasn't going fast at all but ended up giving myself a start when my boot / peg scraped the tarmac, but not my knee.

Plans for Round 4: http://prairiedogracing282.blogspot.ca/2014/08/round-4-is-almost-here.html

That was great fun. A few exciting moments in there! I loved how you managed to smoke most of the field in the corners even though you were clearly at a power:weight disadvantage. Nice.

Thanks Hotfoot. I write them mostly for myself but it is great to know that some other folks enjoy reading them. And +1 on the "odd shaped accessories". It is surprising how much trunk volume needs to be available to accommodate a steering head stand.