rchase
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Posts posted by rchase
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Robert, take a look at your right arm and your body. What is your left knee not doing?
It's not touching the bike at all.
The one good thing is I completely understand the why now. I'm just glad I saw it in a photo rather than with a visit from the pavement gods.
I hope others find this photo useful. It's slightly embarrassing for me to post it.
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Part of my trouble is being out of shape and not really flexible as I should be. That's the negative part of having a desk job where I work from my house. I'm going to make a much more conscious effort to get out more and get moving. I'm also going to practice moving around on my bike on the stands so that I get the muscle memory and get used to the sensation.
While you are transitioning and on the bike it seems ok "just for a second" but as the speeds increase I can see how it would really become a huge problem. When your weight settles the suspension compresses and you are also putting input into the bars as it's one of your points of contact supporting your upper body. At higher speeds I could see this actually upsetting the bike enough to even cause a loss of control. That loss of control could be a handful if you are "standing on" the bike. One other thing to worry about. What if your foot slipped off a peg.
Seeing that photo was a "holy @**$" moment for me and made me realize the problem of "doing it wrong".
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When I took Level 3 Dylan spent a huge amount of time with me trying to make sure I had the Knee to Knee and Hip flick down. For some reason or another I preferred to lift myself from the seat and settle back into the seat in the quick transitions. Until I saw what it looks like.
Here's a photo of me snapped during a transition using the wrong technique. It feels ok on the bike but looks absolutely terrifying from the outside. My weight is on the pegs and I only have 4 points of contact with the bike two of which are the bars. How stable is the bike in this photo? I'm going to force myself to do it the right way from now on!
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There was no accusation there... just thought it would help keep things from getting overly complicated. There's some other really great stuff in that thread too. I'm very much a "why" guy myself.
Benny
Ah. I kinda missed those quotation marks. That's what I get for reading the reply via e-mail rather than on the forum.
I really appreciate the reference though. I think it's about time I started thinking about tire pressure a bit more. Reading that will be helpful and perhaps answer a lot of questions.
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BOTH front tires, if you have them - I'd like to see the pro tire, too.
The front on the pro bike is going to be a challenge. I only snapped a photo of the rear because it was so deformed. :/
I can get a photo of my bike shortly. It's still in the trailer in a front wheel chock. I have not unloaded a thing.
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Robert, what were your cold pressures?
I was running 31 front 30 rear. These pressures were set in the morning when it was a "cool" 80 degrees out. The ambient temp rose to 101 degrees and the track temp itself was 140 degrees with the hot Georgia sun beating down on it. I really should have revisited the pressures once the temp rose but I was caught up in the moment and I also had no idea how to set a hot pressure.
Benny. Don't get the wrong idea. I'm not one of those tire pressure nuts who want to tinker around with pressures all day. I would rather "set it and forget it" as it's one less thing to deal with. The riding is much more interesting to me. I'll check out that thread and see if it's a better resource. The big problem I have had in the past is most of the tire pressure discussions I have seen online have been "do this do that" rather than fully explaining end to end the underlying science. I'm hard headed and need to understand the "why".
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I'll chime in about Roberts bike. It's a 2014 S1000RR that is set up for his weight and adjusted for him.
Now that his pace and riding style are improving he may soon need to revisit his suspension settings. Maybe a quick trip back to the shop (in the trailer) before the street wears off all the hard work and fun from last weekend.
Hey That's an awesome idea Jeff!
The other "problem" is I'm running completely stock suspension and I have yet to start tinkering with tire pressures. The Asphalt got to 140 degrees both days and I set the pressure in the morning and never revisited it. As the day progressed I could "feel" a lot of unhappy behavior in the back especially over the bumpy bits. I'm going to start reading up on the whole hot/cold tire pressure adjustment stuff soon. There's too many schools of thought in regard to that and it gets confusing FAST.
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So. I'm interested. In regards to design philosophy, are the cast frame decisions that some Japanese makers made based on weight, flex, price or perhaps a combination of all three?
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There has been instances where a hi speed lowside caused the bike + round protruding slider to spin and hit said riders, with disastrous results...
So an interesting thought here. I wonder how many of those bikes were equipped with additional sliders other than just the frame sliders? One point of contact rather than several can cause all sorts of unexpected problems.
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I'm not sure about that. I saw a completely demolished Kawasaki at Barber once after a nasty oil slick on the track. I could not even tell what model it was because it was so broken.
Personally which bike crashes better is not very important to me. I care a lot more about myself than any of my bikes and I'm probably a lot less durable than any of them. Not crashing at all is a much better solution. Sometimes it can't be avoided I admit.
Making an investment in education and training is a good first step to prevent a LOT of crashes. There's another benefit as well. Confidence and speed.
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Good stuff so far. You guys have guessed that this track has a lot of right hand turns. I'll give some more information. The Asphalt temp was 140 degrees and that tire was ridden "all day" for two days.
Here's my tire on the same track ridden for a small handful of sessions at a MUCH slower pace. Gotta love the little white rocks though.
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So this weekend I was chatting up a fellow S1000RR owner in the paddock at a track day. We were talking about frame sliders and my Tecbike belly pan. Unfortunately the session after our chat he crashed. His bike made it through his "agricultural experience" without a single scratch or ding.
As for the broken frame. Just to give you an idea of the cost one of my R6's developed a crack in the frame. I'm somewhat emotionally attached of the bike because it's the first sport bike I ever bought. The used frame was $1000+ and the labor cost to replace it will likely be $1000+ as well. This is for a 10+ year old "throw away" R6. The bike has to be completely disassembled for replacement. You can get frames very cheaply but once you need a title to be able to register the bike the costs go up FAST.
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Ok. Here's one for you tire reading guru's.
This tire is mounted to the back of a BMW S1000RR that belongs to a professional racer. What can you tell from the wear?
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I believe (and really, it's just that—a belief) that the long sliders are far more apt to cause a flip than ones that are lower and more rounded. I have the GB Racing "race" sliders for this very reason (they also make a taller version for street—my thinking is this is because street riders care more about their plastics).
The big toilet-paper-roll sliders seem like trouble to me.
I tend to agree with you on this. I went with the Woodcraft sliders. They are lower than the ones you see on the street and have rounded edges.
I think the street going ones are so large for a couple of reasons. First is the idea of protecting the bodywork which is a false economy if you crack the frame. The second really is just appearance. Frame sliders tend to add at least 10-15mph of speed capability to any parked motorcycle especially when teamed with lots of stickers and a set of track take off's.
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You can't really predict physics. Sometimes they help and sometimes they don't. It really depends on the type of crash and the situation if they are helpful or not. Motorcycles aren't crash tested but there is some general knowledge out there from other people's experiences. If you look at most race bikes they are equipped with sliders. That's good enough for me.
The underlying purpose of them is to protect frames and engines rather than bodywork. Cast aluminum motorcycle frames will easily develop hair line cracks if they are stressed the wrong way. It's difficult to weld cast aluminum and VIN numbers are tied to the frame making replacement complicated and expensive.
If you think about it it's all about momentum. If a bike has so much momentum that it flips because a frame slider catches what stops a bar end or a rear set from also hurling the bike in the air? Nothing you can do will overcome that momentum when you have a bike moving at speed.
Personally I think sliders help protect the bike's most important parts during a crash. One of the first things I did was order sliders when I took delivery of my new S1000RR. I hope I never need to find out how effective they were.
P.S. Frame sliders by themselves are not as effective as a comprehensive set of sliders for a bike. Engine case guards, Axle sliders and other protective parts all work together to minimize the damage when things go sideways.
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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)?
Good point. The problem with most of these comparisons is it's never a fair comparison if you dig deep enough into the circumstances. There's always some minor detail that invalidates a fair comparison.
I have seen people on motorcycle forums complaining that their favorite bike performed poorly because it was tested towards the end of the day when the test rider was tired. A valid point perhaps and perhaps a bit of denial. The reality is it's impossible to know "absolutely".
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I suppose most of this theory goes out of the window when you are charging around the mountain?
Hee hee, I think ALL theory goes out the window, and you are left with pure REALITY!
Isn't that why they do it?
That's certainly true.
As for the theory. It's still applicable and useful regardless of where you ride. It's just a question of keeping your SR's in check. Human beings have not changed much in 100 years. We wear different clothes and are aware of different riding techniques but we all have the same hot button issues that tie into the internal wiring and programming of our minds that make us freak out and react in the worst possible ways. We are the weak link in the man + machine chain.
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Amazing.
The front tire looked almost completely gone. He corrected that, stabilized the bike then reduced his lean angle and lifted his full weight with his lower body. All of this while every SR known to man was screaming at him and with the stress of a "blown corner" potentially affecting his position.
Photos like this bring new meaning to the concept of "working under pressure".
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Riding Technology.
That's true even though there has been some evolution over the years. What's stuck with us over the full amount of times is the same SR's that people were dealing with over 100 years ago. They tend to get much bigger and scarier as the bikes get faster.
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While the bikes have come a long way what factor has not changed much between then and now?
I seem to remember a section in one of Keith's books that mentioned this exact point.
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I was looking up some information on Aerodynamics for some further understanding and found this video. BMW's WSBK team using a wind tunnel to help the rider find the best position for the straights. Very interesting.
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Hotfoot and Slasher. Thank you guys again for your advice. With the new windshield I just installed on my bike and some of your great advice I'm going to face that wind blast on the long straight at Robeling Road next week. I plan on working on my tuck and plan on revising my seating position to take advantage of the back rest as well.
Photo of the new windshield. Much taller and a snap to install.
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Hey Nic. It's always nice to see someone follow their dreams. I'm glad to hear you are going to try your hand at racing. I'm looking forward to seeing the blog.
Age is a meaningless number anyway. Some inspiration for you. Here's a well known 80 year old by the name of John Surtees riding a vintage MV at Barber.
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Hey Las. Welcome to the forum. Lots of helpful advice and resources here from fellow students and coaches.
Barber is a spectacular track and I'm also glad that CSS teaches there. Have you decided on any dates yet? Barring any last minute schedule problems I'll be there next year myself.
Knee To Knee Why It's Important!
in Cornering and Techniques
Posted
Well. They are much lighter than I am and are riding on top of suspension that costs more than my whole bike.
I have done it correctly before at the school and it does make the transition much smoother. My goal is to do it the right way.