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  1. 3 points
    MotoGP riders are typically trying to dial up as much engine braking as possible. They can also dial it in or out for specific turns by GPS. If you are riding a track that is very "stop and go" with a lot of braking zones, I would dial it up. If it is a flowing track with transitions, I would use less engine braking so the bike does not pitch forward if you feather out of the throttle in a transition.
  2. 2 points
    Good observation on your part on the no-brakes format. Riders mostly over-brake when they start to add more/harder braking, and loose entry speed. Your overall goal if good, nothing wrong there; the other steps that go in that direction are smaller bites one would take to achieving that. As for braking and then realizing you could have gone faster...that's a not uncommon situation that occurs. Front brakes are the most powerful thing on the motorcycle, consider that a much smaller single rear brake can stop the engine. How about approaching the braking with the idea its a fine adjuster, capable of great force, but in the end, getting the entry speed correct for you (no too slow or too fast) is the key. There are a few pieces to this, we can work on them for sure. Best, Cobie
  3. 1 point
    Hey guys. I wanted to share some videos I made of me analyzing data of of my lap vs WSBK rider who is also riding my bike around Chuckwalla CW direction. So far I have made 3 videos that are very basic, but a good place to start because they are simple and hopefully easy to understand. My qualifications: I used to race cars, and we were very heavy into data analysis. I also spent many hours with crew-chief of Tech3 and Data Engineer for Gresini which we covered in detail all aspects of data acquisition for motorcycles. Software and data acquisition system: "2D Data Recording" (used on all moto3, moto2 and many MotoGP machines) The videos should be watched in order because they sort of "build" on top of each-other. Video #1 (time spent at lean) https://youtu.be/aJ_E-sUxJc8 Video #2 (roll speeds) https://youtu.be/aUDGNg2WDDM Video #3 (how it is possible that my roll speed is lower and my lean angle is higher) https://youtu.be/02q4I4xnyLc Future videos will all compare WSBK rider lap with my own (order not yet decided): - Roll Rates. How fast do we add or decrease lean angle. I will also cover counter steering, and how it works - Changing Radius during cornering. Entry, neutral, exit type corners and V-type - Motorcycle dynamics (will be many separate videos). Lean angles converted to G's. How to calculate lean angle from radius and speed and the other way around. What are G forces. Braking G's, acceleration G's, combined G's (traction circle). Why a bike does not fall and a self correcting system (rake, trail, offset). Anti-squat. Tire coefficient of friction. Camber thrust. - Focus on entry phase of corners - Focus on mid corner phase - Focus on exit phase - Suspension setup by suspension speed histogram to adjust rebound, compression scientifically. - How to find more time at a given track without a reference lap. - Oversteer & understeer - Sprocket sizes and gear simulations on the software. - Throttle acceptance - Xavi Vierge data analysis from Valencia Qualifying 2016. This will be fun. He brakes at 0.9 G's at 50 degrees lean! Woohoo! - Contact patch. Does a bigger contact patch actually provides more grip? (this one will really piss some people off) - Ideal Tire working temperatures, how we can find them, and how we achieve them. - Yaw
  4. 1 point
    Interesting! The third video may also show why quick steering is so beneficial since it allows the choice of a more efficient line. It also explained how one rider could corner at a given speed around a corner, fully decked out, while another can go faster and barely graze a peg feeler; different lines around the corner that require different amounts of lean for the same speed. Thanks for clarifying that. BTW, you may want to check your tags as I get a lot of animal video suggestions when watching yours, but nothing relevant.
  5. 1 point
    Hey Faffi. The article from cycleworld pretty much explained what is happening and this phenomenon of why moto3 corner faster than motogp so I suggest you read it very carefully. The MotoGP video is leaving out some important details in order to glorify and promote moto3 in with this concept of "hey, moto3 still has its strong points, they corner faster". Sort of like - rooting for the underdog. The reality is that moto3 bikes do not do anything better than motogp bikes besides maybe the flick rates (from side to side). They certainly are NOT capable of cornering at a higher speed than motogp bikes and the article from cycleworld alluded to that fact. I'll try to explain again. Imagine a motorcycle doing circles in a parking lot. Constant radius circles non stop at a constant speed. The higher the lean angle, the faster these circles can be negotiated regardless of the weight of the bike. At a certain lean angle, a given motorcycle tires would start to slide. This is dependent on the coefficient of friction of the tires. If the tire coefficient of friction is 1, anything past 45 degrees would result in a slide, and if not corrected, a fall. If the tire coefficient of friction is 2, anything past 63.4 degrees would result in a slide, and if not corrected, a fall. We know that motogp tires have a higher coefficient of friction compared to the japanese made KR133 dunlops used by moto3. So moto3 bikes can not lean as far as motogp bikes. The article explained this by how moto3 riders do not drag their elbows, but motogp do this frequently, and even tuck in their elbows a bit to allow even MORE lean angle. I will try to get moto3 data for Valencia and compare it to moto2 data to compare max lean angles and see which achieve higher. I know moto2 usually do around 56-58 degrees. Motogp can get to 60-63. So why do moto3 bikes have a FASTER mid corner speed than Moto2 or MotoGP? The article also explained this. It's because moto3 bikes do not have high acceleration potential, so their biggest "tool" for speed is momentum and mid corner. Any 1mph they overslow in mid-corner, is a 1mph they will very much struggle to get back. So moto3 riders choose to put emphasis on the corrector strengths of their machines by choosing lines that have the absolute highest radius. MotoGP riders will purposefully create a tighter radius in the entry part of the corner, in order to greatly increase the radius on the exit portion, so they may unleash their 260hp. If a MotoGP bike used the exact same line as a moto3 bike, it would not be competitive compared to other MotoGP bikes as it would not be able to get on the gas early and hard. But its mid corner speed would be greater than that of the moto3 bikes because it is able to achieve higher lean angles due to its greater tire coefficient of friction. Please remember, for constant radius, the only thing that can increase speed is lean. Maximum lean is maximum lateral G's the tire is capable of. Weight of the machine, has nothing to do with it. So what to do? Get stickier tires and you can lean more and you can have more speed at the max lean portion of every corner. Hope this helped clarify.
  6. 1 point
    Trying to find whether the smaller bikes corner faster - or not - I found this: https://www.cycleworld.com/sport-rider/motogp-extreme-lean and
  7. 1 point
    He talks about racing lines, braking, battling vs riding alone and more https://www.crash.net/motogp/news/915429/1/vinales-alone-i-can-make-lap-time-then
  8. 1 point
    I hope the current D208 are something else than the Sportmax D208s I had on the CB400 back in 2013! Most slippery rubber I have ever ridden on, by a big margin. They were original equipment on the DRZ400 motard allso, and may have worked on 100F sunny days, be we do not get those here. Ever. Sport touring tires work quite well when cold, and also warm up much quicker in my experience, compared to sport rubber. Even touring type bias ply will out-perform sport rubber under some conditions. I'll bet that on a day with 20-30F, something like a set of Metzeler ME77s will offer a LOT more grip than any modern sport radial made. At least with street tire pressure. In short, there is nothing wrong with sport rubber, but they are made for a purpose. Riding on public roads at respectable (as in legal) speeds in chilly temps are not such a purpose IMHO. In fact, even on a hot day, at a sensible pace for public roads, I doubt any pure sport tire will offer the grip of a sport touring model.
  9. 1 point
    Oh yes, if you were riding the Ninja 300 you will definitely feel a lot of difference; I rode a Ninja 400 recently and I was amazed by how much it wanted to decelerate when I let off the gas - and I discovered that my roll-offs were NOT as smooth as I though they were (see Throttle Control rule #2)! On the S1000s you can adjust the engine braking amount; after switching from another bike to my S1000rr where it is set very low it takes some getting used to, since I feel like I am free-wheeling into the corners, but it is a good learning experience as it makes me pay a lot of attention to my entry speeds. Personally, less engine braking helped me bring up my entry speeds (not always entirely on purpose!), and since I like the suspension set very soft in the front it minimizes (as Dylan said) the bike pitching forward when I roll off on flowing corners. I had trouble with the Ninja on that point, it would decelerate so rapidly on engine braking that it would compress the front. If nothing else the change to less engine braking may break some habits on entry speed and roll off points and force you to take a new look at judging the approach to higher speed corners.
  10. 1 point
    In October of 2017, the year I posted this, I had a race ending accident at The Barber Vintage Festival. Race practice might have been an ominous sign for things to come when I nearly crashed on a team Triumph Thruxton going about 100 mph. I had been putting in some good lap times and needed about a 1/2 a second more to put in the top three. I was approaching turn 9 and 10 knowing I would need to get the bike turned quickly to carry the speed and to keep the bike off the rumble strips on the outside. I was finishing my steering input when the outside clip on snapped against the gas tank. I had no way to control the bike as I headed for the gravel on the outside of the track. I didn't have much time to think about it but the option of bailing didn't seem like a wise move at the time. I went through grass, pavement, gravel and then grass again. I had slowed to about 60 when I noticed the reflection of blue sky in the grass ahead. Any of you that have ridden or raced at Barber know how George likes to keep his landscaping nice and green. There was reflection of the sky in the grass ahead about three inches of water. I hit it and it was like an explosion. People who saw my antics wished the ride had been recorded. I survived it keeping the bike upright and getting it back to the pits. Lesson: when you are riding on someone else's machine double and triple check the levers, clip on's, rear sets etc etc etc. The next day was my Sounds Of Thunder 2 race with 70 riders lined up on the grid. I was racing on my modified SV650. I was on the 9th row. My strategy for the race was to get a good start and try to hang on the leading pack. I wanted to get into the 1:37's which for me on a SV650 was a respectable lap. My previous fastest was a 1:39 in practice. I got a great jump and was headed down into turn one when I saw a blur coming in from my left side taking me out. I remember being launched over the left clip on then nothing but the most extreme pain I have ever felt in my life lasting for no more than a millisecond. I remember holding someone's hand and hearing sirens but not able to make out any faces. I remember telling them not to cut my leathers. I have two close racing buddies, one an orthopedic surgeon and the other a neonatal surgeon. They were both on the track when this happened. One of them, the neonatal surgeon, knew that he would have to keep me close to try and better my lap times so he saw it all. He thought I was dead. He went against race protocol resting his bike against the Armco barrier and ran to me. He said he pulled up my visor to see if I was breathing.The rider who caused the initial accident lost his front coming into turn one ejecting me. The rider who did the damage had no place to go. He basically did a stoppie on my chest then releasing the brake lever rolling off me to have the rear wheel land on my chest. I had what they call a flailed chest with 10 broken ribs, a broken sternum and a punctured lung. I had to wait three days for surgery to install titanium plating to hold my ribs together. I had some issues with pneumonia after the surgery spending 12 days in intensive care. My biggest fear going through this was that I would be an invalid and before the advent of the titanium plating, I would have been. I would have much rather died doing something I love than be a burden. The good news is a never gave up. I am almost good about 85% lung capacity and missing a muscle or two. I'm working out at a local gym and riding a Peloton at home. I also have a mountain bike that I take for long rides communing with nature. I have ended my racing career or should I say my wife has ended it :) I loved racing but not enough to destroy a marriage. For me there were two choices, life or death no in between. I am physically fit enough to ride competitively and if I could talk my wife into it, my goal would be the same, to better my craft every lap, to be the best that I could be. There's nothing like the feeling of beating your previous best lap time and there's nothing like being told "man, you can ride." I am one of those guys now, relegated to telling stories and helping with bike stands and tire warmers as others ride out to the track. Thank you, Cobie and all the rest of those at CSS that coached me a long the way. Great memories.
  11. 1 point
    On the road - downhill, off-camber decreasing radius corners are the ones where confidence is lowest. The main issue is finding a line for the decreasing radius is usually always on the camber, where you would have normally turned in if it wasn't a DR turn. The corner in mind starts flat then drops away so there are suspension and weight forces in play too, making the bike 'go light' proir to the apex. I don't tend to quick flick and use more upper body movement to compensate but perhaps this isn't correct? ps. 'downhillness' - say it with conviction and you've coined a new word! (decline?/downward elevation?)
  12. 1 point
    Hello all, I've been a fly on the wall for a while now - I appreciate all the knowledge and discussion here. Recently signed up so I could ask some questions and participate. Began riding on a 1983 Honda z50 when I was six and I've been through quite a few bikes since (all dirt until I was in my 20's, now I'm in my 40's and mostly ride street and track, still get on the dirt from time to time though). I've been to a two-day camp and a couple single days with CSS and can't say enough great things about what Keith started and the CSS team carries on. The closest thing to race experience I've had was working as a Corner Marshall at the 2018 MotoGP event at COTA - on Comms to race control at T14 for four days. It was great to see the action up close and participate in the safety of the races. I live outside Austin, TX and about 35 miles from COTA - that and Harris Hill are my local tracks, haven't made it to MSR Cresson or Houston yet. I've been on the fence about getting into CRMA - family and other passions make the financial side difficult to justify. Anyway, greetings, I appreciate the opportunity to become a part of this online community.
  13. 1 point
    Cobie, Here's a post that I was working on but decided not to publish it...that is until you asked (minor edits made). Hotfoot- Sorry for the short response above. I'd intended to PM you about it later and just forgot. I didn't want to go too much into an answer at the time because I still want to maintain a modicum of online privacy & anonymity and I was still raw about the embarrassment. Confession being "good for the soul" and all that jazz. I hope you understand the fountainhead of my tepidity. A lesson (story) and question on confidence This Friday morning I learned that 50F is still too cold to ride. I saw that we would have a break in the cold weather, I decided to commute to work. I had been watching the forecast a couple days and Thursday was warmer than forecast so I reasoned I could relax my 60F minimum. Data indicated that at 6a it was 50 at a local weather station and the forecast high for the day was 60F. Preparing for the day, I went online last week and renewed the registration sticker and verified my insurance policy’s coverage status: FULL COVERAGE. I’ve got a lot going on with 9 motorcycles and 4 riders in my household - it’s too much to keep it all in my head. Life and maintenance was simpler with one bike and one rider. Knowing that I purposely over-inflated the tires while garaged, I pressurized the pump and readjusted the tire pressures on the Q3+ to 34F/36R Thursday night. I hadn’t ridden my CBR1000RR in 2018 but about 100 miles or so, spending all year racing my stock XR100. And besides, just because I’d entered it into Bike of the Month doesn’t mean it’s a garage/trailer queen. It’s meant to be ridden, right? Right! Well, I didn’t make it off my street when the rear tire broke loose in the right turn about 15MPH. Too much lean angle and not enough Joules (heat) and I witnessed it sliding and rotating away from me in the intersection of my subdivision, coming to rest on the footpeg and frame slider. The distance of my trip was approximately 200 feet from my driveway. My post-accident review Sunday Morning revealed the effect of the rising slope of the adjoining street on the right side was adding lean angle. Plus, I also know that I began to crack the throttle a tad too early on the rev-happy I-4 engine. We have the kind of pavement that looks like pressed rocks with deeply visible gaps where water, sand, or what may have been present...salt granules like to hide. My heart sank. And I could feel my back already begin to tense up. I didn’t even feel like picking it up for fear that I would be in horrible back pain later and the horror of the damage to my baby. I mustered the courage to find that the crash protection on the bike did its job. <$50 and she’ll be good to go! However, I still needed to get to work. I went back home and changed my pants (LoL). I made the foolish decision to not wear my riding jeans and tore a hole in my corduroys and skinned my knee. So I bandaged my knee, changed into my riding jeans and back out I went. But it wasn’t the same. Something happened to my mojo... This isn’t my first experience putting a bike down. But it’s a different experience with this bike because it’s my favorite. I think it’s because I put a lot of time, energy and money into customizing it to make it uniquely mine. I have wanted this bike for years before I bought it- even denying that I wanted it, until when it was offered to me preowned at a price I couldn’t refuse. My commute to work was tentative. And I don’t like the way I felt about it. My ride home was at 10p was uneventful and it felt like I had good traction. I wanted to put the crash behind me more than I was able to at the moment. I'll address that later...
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