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Old 11-16-2017, 10:23 AM   #1
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Lowside Thunderhill Turn 14


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Old 11-16-2017, 01:42 PM   #2
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looks like u just kept adding lean angle until the front tucked. i really doubt u needed your line to be that tight, even though u were a little wide.

i cant tell what u were doing w/ the brakes. it looks like u were already off them a lot (too much). but the braking bumps make it hard to be certain.

your lean angle changes are very abrupt in the other corners, both when adding lean angle and taking it away. def try to smooth those out.

u ok?
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Old 11-16-2017, 02:36 PM   #3
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looks like u just kept adding lean angle until the front tucked. i really doubt u needed your line to be that tight, even though u were a little wide.

i cant tell what u were doing w/ the brakes. it looks like u were already off them a lot (too much). but the braking bumps make it hard to be certain.

your lean angle changes are very abrupt in the other corners, both when adding lean angle and taking it away. def try to smooth those out.

u ok?
this was the first session of the day and it happened right at my brake marker - the last cone was my marker and the bike almost took it out

since it was cold and there was limited traction i was getting more braking done before tipping in - was that the wrong thing to do? lean angle changes were abrupt because of this i believe

i dislocated my shoulder but was able to get it back in before control rider showed up. bike started and all controls worked so i rode back into pits, used zip ties and a drill (sorry $$$ fairings) and passed tech and rode another two sessions. my head fairing stay broke, subframe tweaked, tail smashed, gas tank dented, and of course fairings are toast.

ultimately i believe that i was too abrupt getting on the gas which unloaded the front. this hadn't happened before because grip levels previously were sufficient to cover my poor technique

being in slick -4 didn't help either...

here is the 'full' session

youtu.be/XhRLWuUMsbY
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Old 11-16-2017, 06:33 PM   #4
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wut? brake marker? do u mean "let off the brake" marker? we need a new term for that because "brake marker" means where u get on the brakes.

tucking the front is common at the let-off marker because the front tire is as unloaded as its going to get. also if u let off too quickly and your rebound damping is too fast, the front tire can sort of jump off the ground too. adding further lean angle after this didnt help either. thats strike one.

i didnt hear u touch the throttle at all. if u did and did so aggressively, we can call that strike two. dont blame the map setting, u know it was set there

your 3rd strike is all that putting around u did in the laps prior. getting stuck behind riders, short shifting, barely using the brakes, etc. even if u run warmers, a lot of your tire temp was gone after those laps. plus u hadnt really used the right side since T5a nor w/ any good braking that entire lap.

personally, ive crashed more times in the cold by braking less and more upright. the front tire loses heat. its not loaded as much so u have less grip. u try to or accidentally carry more roll speed because of the lack of braking, which requires more grip that u dont have. its all bad news bears.

glad u arent more hurt and the bike is alive. fairings are the first thing i put on any track bike.
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Old 11-16-2017, 07:51 PM   #5
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wut? brake marker? do u mean "let off the brake" marker? we need a new term for that because "brake marker" means where u get on the brakes.

tucking the front is common at the let-off marker because the front tire is as unloaded as its going to get. also if u let off too quickly and your rebound damping is too fast, the front tire can sort of jump off the ground too. adding further lean angle after this didnt help either. thats strike one.

i didnt hear u touch the throttle at all. if u did and did so aggressively, we can call that strike two. dont blame the map setting, u know it was set there

your 3rd strike is all that putting around u did in the laps prior. getting stuck behind riders, short shifting, barely using the brakes, etc. even if u run warmers, a lot of your tire temp was gone after those laps. plus u hadnt really used the right side since T5a nor w/ any good braking that entire lap.

personally, ive crashed more times in the cold by braking less and more upright. the front tire loses heat. its not loaded as much so u have less grip. u try to or accidentally carry more roll speed because of the lack of braking, which requires more grip that u dont have. its all bad news bears.

glad u arent more hurt and the bike is alive. fairings are the first thing i put on any track bike.
Having watched the full video, I agree with Stang, those warmup laps did anything BUT warmup the tires. They were slow, puttery laps. You should have been braking harder and accelerating harder. My warmup laps contain some of my hardest braking and accelerating i can get (while straight up and down) to put heat in the tires before i start pushing lean angle and corner speed.

Also first few laps had some camera sputtering during/between turnin/apex which tells me you were probably a bit tight on the bars, maybe you didn't do any stretching/warmup of your body (you need warmup too!) or were a bit nervous/timid that morning because of weather.

Suspension also has to warmup like tires, and that affects your grip levels.

My first race at sonoma was on a cold suspension. the first 2 laps of that race were SCARY because of cold suspension.

Looks like everyone was a bit nervous/timid that day, maybe because weather. A group looks soft/slow. I also didn't like your line and felt like you were missing your entry and exit apexes.
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Old 11-16-2017, 08:40 PM   #6
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wut? brake marker? do u mean "let off the brake" marker? we need a new term for that because "brake marker" means where u get on the brakes.

tucking the front is common at the let-off marker because the front tire is as unloaded as its going to get. also if u let off too quickly and your rebound damping is too fast, the front tire can sort of jump off the ground too. adding further lean angle after this didnt help either. thats strike one.

i didnt hear u touch the throttle at all. if u did and did so aggressively, we can call that strike two. dont blame the map setting, u know it was set there

your 3rd strike is all that putting around u did in the laps prior. getting stuck behind riders, short shifting, barely using the brakes, etc. even if u run warmers, a lot of your tire temp was gone after those laps. plus u hadnt really used the right side since T5a nor w/ any good braking that entire lap.

personally, ive crashed more times in the cold by braking less and more upright. the front tire loses heat. its not loaded as much so u have less grip. u try to or accidentally carry more roll speed because of the lack of braking, which requires more grip that u dont have. its all bad news bears.

glad u arent more hurt and the bike is alive. fairings are the first thing i put on any track bike.
Yea it was my off brake marker

Good point, I know I need to be smooth off and on the brakes same as throttle, but easier said than done. I need more practice. Lots and lots of practice I agree that adding lean angle after off brake marker is a mistake since you are unloading your tire, which reduces contact patch, at the same time you are reducing contact patch by increasing lean. I probably got away with it all summer because I had warmers and slicks although this crash day I was not using warmers for the first time since it was going to rain

My initial impression after the crash and throughout that day was that I jumped on the gas too much. After I passed tech again I rode another two sessions and I noticed that there was a gouge in the asphalt from my peg from my crash. The gouge started right on my off brake marker. I made sure to brake past that gouge the rest of the day but until now I was wrong in thinking that it was my poor throttle management that caused the crash. I now agree with you and think that it was a brake timing mistake

Yea I was riding sedate and purposely didnít pass the group in t14 on the prior lap because of temperatures! Same with t1 right after, played it safe all the way to 9 since t5 was cold and they said no passes in 7 or 8. After I made the pass in t9 my lizard brain took over and I forgot some stuff like the temperature lol

It seems counter intuitive to need to stay on the brakes to keep from low siding! Is that more or less necessary in t3? Is this right ďOff camber dictates less max pressure but timing remains the same as On camberĒ?

Well my wife didnít see the point in track fairings since Iíd never crashed before

but more seriously I am extremely grateful that I wasnít hurt worse than I was
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Old 11-16-2017, 09:02 PM   #7
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Having watched the full video, I agree with Stang, those warmup laps did anything BUT warmup the tires. They were slow, puttery laps. You should have been braking harder and accelerating harder. My warmup laps contain some of my hardest braking and accelerating i can get (while straight up and down) to put heat in the tires before i start pushing lean angle and corner speed.

Also first few laps had some camera sputtering during/between turnin/apex which tells me you were probably a bit tight on the bars, maybe you didn't do any stretching/warmup of your body (you need warmup too!) or were a bit nervous/timid that morning because of weather.

Suspension also has to warmup like tires, and that affects your grip levels.

My first race at sonoma was on a cold suspension. the first 2 laps of that race were SCARY because of cold suspension.

Looks like everyone was a bit nervous/timid that day, maybe because weather. A group looks soft/slow. I also didn't like your line and felt like you were missing your entry and exit apexes.
I thought thatís what I was doing!! turns out I was doing the opposite and keeping the heat out of the tires

Watching the video I was surprised to see the amount of front end movement, I donít remember feeling it at all? Iím aware of the need to be light on the bars, I know my inside arm is good since I can take it off the bar and I think my outside elbow is locked on the tank so itís good too. It kind of looks like Iím pushing the front into most corners from a too early off brake marker? Or maybe the movement is normal? Dunno

It was the first session of the day in bad weather but yea I was shaking my head when dude picked his ass coming up on t14 maybe thatís what set me off
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Old 11-16-2017, 10:10 PM   #8
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My initial impression after the crash and throughout that day was that I jumped on the gas too much. After I passed tech again I rode another two sessions and I noticed that there was a gouge in the asphalt from my peg from my crash. The gouge started right on my off brake marker. I made sure to brake past that gouge the rest of the day but until now I was wrong in thinking that it was my poor throttle management that caused the crash. I now agree with you and think that it was a brake timing mistake
As you may know by now, you werenít on the gas when you last the front, as the bike was still slowing. No idea how much bar pressure you may have had at that point, but if you were leaning on the inside bat, that could contribute to losing the front. Had you been relaxed on the bars and starting to roll on the gas there, it would have relieved the front of both weight and cornering load.
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Old 11-16-2017, 10:52 PM   #9
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As you may know by now, you werenít on the gas when you last the front, as the bike was still slowing. No idea how much bar pressure you may have had at that point, but if you were leaning on the inside bat, that could contribute to losing the front. Had you been relaxed on the bars and starting to roll on the gas there, it would have relieved the front of both weight and cornering load.
Thank you for the response (goes to everyone) appreciate your time

That sounds right, stang did say that I was increasing lean angle which implies bar input. Watching it again it does look like me tightening my line as the front tucks.

What is the minimum force into the inside bar(or outside I suppose) which could cause the front to tuck in this situation? What is the maximum amount of weight on bars in general between the off brake marker and on gas marker?

Would it be a good summary to say that I should focus on my lines while minimizing bar input?
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Old 11-17-2017, 12:02 AM   #10
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What is the minimum force into the inside bar(or outside I suppose) which could cause the front to tuck in this situation? What is the maximum amount of weight on bars in general between the off brake marker and on gas marker?

Would it be a good summary to say that I should focus on my lines while minimizing bar input?
lines are very important imho. Being able to hit your apexes are very important to consistency and predicability. One of ken hills first order of the sport is eyes and bike placement.

As you get faster and more consistent add in new skills, trailing deeper to the apex, smoother roll ons, more roll speed, different lines (still hitting your apexes!) etc. You can mix and match, work one on each session or each trackday.

You should always focus on staying loose and smooth with good eye focus. It helps everything, and if you're not loose or smooth or your eyes arent engaged, all the other skills will not help much.

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Well my wife didn’t see the point in track fairings since I’d never crashed before

but more seriously I am extremely grateful that I wasn’t hurt worse than I was
hotbodies race fairings are 50% until end of november, just saying

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Old 11-17-2017, 07:20 AM   #11
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Thank you for the response (goes to everyone) appreciate your time

That sounds right, stang did say that I was increasing lean angle which implies bar input. Watching it again it does look like me tightening my line as the front tucks.

What is the minimum force into the inside bar(or outside I suppose) which could cause the front to tuck in this situation? What is the maximum amount of weight on bars in general between the off brake marker and on gas marker?

Would it be a good summary to say that I should focus on my lines while minimizing bar input?
In T14 you don't want to be pushing on the bars at all if you don't need to. It looked like you went in deep, and tried to hit your apex anyway with sudden and sharp correction. Big mistake in the cold. Treat those first two laps like you are riding on ice, and slowly pick up speed. Next time just miss your apex, at that speed it doesn't matter.

Honestly, the best thing you could do is ride a couple rain days. Then you will get an understanding of diminished traction.
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Old 11-17-2017, 08:26 AM   #12
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lines are very important imho. Being able to hit your apexes are very important to consistency and predicability. One of ken hills first order of the sport is eyes and bike placement.

As you get faster and more consistent add in new skills, trailing deeper to the apex, smoother roll ons, more roll speed, different lines (still hitting your apexes!) etc. You can mix and match, work one on each session or each trackday.

You should always focus on staying loose and smooth with good eye focus. It helps everything, and if you're not loose or smooth or your eyes arent engaged, all the other skills will not help much.

hotbodies race fairings are 50% until end of november, just saying
agree with all you said and i will listen to more ken hill podcasts with bike placement being number 1

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In T14 you don't want to be pushing on the bars at all if you don't need to. It looked like you went in deep, and tried to hit your apex anyway with sudden and sharp correction. Big mistake in the cold. Treat those first two laps like you are riding on ice, and slowly pick up speed. Next time just miss your apex, at that speed it doesn't matter.

Honestly, the best thing you could do is ride a couple rain days. Then you will get an understanding of diminished traction.
Thanks for the input afm199 agree with what you described as happening.

Since this was the first session of the day on the coldest day I'd done so far I should have clarified with an instructor how to get the heat in the tires rather than being first on track.

I agree about riding in the rain being good for me. I was under the impression riding slower in the cold required less focus, oops. It might rain at Sonoma in February but if not I will be in the dirt until then so I am going to soon start learning about this thing called 'diminished traction'.
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Old 11-17-2017, 10:11 AM   #13
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strike 4 was not using tire warmers anyway. tires take more work and more time to warm up when the carcass is dead cold. i suspect from watching your other vids that u were pushing >80% when u crashed. after those slow laps and no warmers, that was def too fast too soon.

its almost always a good idea to minimize your bar inputs. the implications of that are huge. being on line and not needing to correct is the minimum. not using the bars to hang off or transition is the minimum. smooth gradual inputs that arent jerky are the minimum. smooth braking that allows for smooth bar inputs is the minimum. etc. of course, all this is very ez to say and hard to do. but u gotta start somewhere.

another edit: one thing i hope u take away from all the "strikes" is that its usually not just one thing that causes us to crash. we make a bunch of little mistakes that contribute to going down. as u incrementally fix all the strikes and all the techniques, u can go faster. as u improve your consistency w/ proper technique, u can be safer too.
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Old 11-17-2017, 11:43 AM   #14
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strike 4 was not using tire warmers anyway. tires take more work and more time to warm up when the carcass is dead cold. i suspect from watching your other vids that u were pushing >80% when u crashed. after those slow laps and no warmers, that was def too fast too soon.

its almost always a good idea to minimize your bar inputs. the implications of that are huge. being on line and not needing to correct is the minimum. not using the bars to hang off or transition is the minimum. smooth gradual inputs that arent jerky are the minimum. smooth braking that allows for smooth bar inputs is the minimum. etc. of course, all this is very ez to say and hard to do. but u gotta start somewhere.

another edit: one thing i hope u take away from all the "strikes" is that its usually not just one thing that causes us to crash. we make a bunch of little mistakes that contribute to going down. as u incrementally fix all the strikes and all the techniques, u can go faster. as u improve your consistency w/ proper technique, u can be safer too.
yea, all the strikes add up to the crash. it seems like if i was more patient i would have avoided most if not all of the strikes that led to the crash...
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Old 11-17-2017, 03:53 PM   #15
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just found this. the braking part highlights exactly what ive been saying and u already know. there are also a lot of good visuals that highlight the diff btw how u rode in this crash and how a pro would make it through the same corner while going a lot faster.


youtu.be/wI8WpN7aCFM
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