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Old 07-10-2021, 01:37 PM   #16
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I used to be confused when people would ask for help with "lines". Most lines seem obvious enough - exit curb, apex curb, exit curb - and being off by a little doesn't matter for laptimes in B-group. So then I thought it wasn't the line they needed help with, but how to execute that line especially with speed. Now I realize it's both. And if you miss any part of the line or the execution of everything before and after, you are taking more risk and going slower. It's nuts. I need to write a book on why road racing is so hard.
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Old 07-11-2021, 01:29 PM   #17
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One of the problems with having the throttle open while adding lean angle is that as the lean angle gets steeper, your final drive ratio gets shorter (smaller tire diameter at the edge). This can change the torque getting to the tire much more than you might expect from whatever you’re doing with the throttle.

The throttle should be closed until lean angle is set and the bike is on line, whether trail braking or not.
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Old 07-11-2021, 05:14 PM   #18
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Sounds to me like the tire slide started out slowly, no big increase in rpms. You can see where it looks like the op was starting to take a tighter line, then the rear really spun up and he went down. I think the tighter line was the rear starting to come around. Could have caused by a combination of lean angle, tire, but not throttle.
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Old 07-12-2021, 08:45 AM   #19
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Quote:
Originally Posted by Holeshot View Post

One thing I did notice (and it's hard to totally tell w/ the camera angle) is it seems you're on the side of the tire a lot in a given lap. Does this seem the case?
I think it's true statement, and usually I'm pretty patient with throttle application, and waiting until bike is pointing in exit direction.


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Originally Posted by stangmx13 View Post
I used to be confused when people would ask for help with "lines". Most lines seem obvious enough - exit curb, apex curb, exit curb - and being off by a little doesn't matter for laptimes in B-group. So then I thought it wasn't the line they needed help with, but how to execute that line especially with speed. Now I realize it's both. And if you miss any part of the line or the execution of everything before and after, you are taking more risk and going slower. It's nuts. I need to write a book on why road racing is so hard.
That's what upsets me the most - I've been (or was thinking I'm) rigorous about lines and when and how each control should be applied, and messed up line (like I did at Sonoma) is "okay" reason to crash for me, but fail with technique that I was preaching myself... we live, we learn, I guess

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Sounds to me like the tire slide started out slowly, no big increase in rpms. You can see where it looks like the op was starting to take a tighter line, then the rear really spun up and he went down. I think the tighter line was the rear starting to come around. Could have caused by a combination of lean angle, tire, but not throttle.
Yep, it (tire, line) felt alright and all of the sudden it just went... I do believe tire condition contributed, and my skill level obviously not enough to deal with such situation.
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Old 07-12-2021, 09:04 AM   #20
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One of the problems with having the throttle open while adding lean angle is that as the lean angle gets steeper, your final drive ratio gets shorter (smaller tire diameter at the edge). This can change the torque getting to the tire much more than you might expect from whatever you’re doing with the throttle.

The throttle should be closed until lean angle is set and the bike is on line, whether trail braking or not.
Does it? Ive never been able to fully decide one way or the other. Assuming maintenance throttle, will someone's speed change as lean angle changes? Im leaning towards 'no'. The drive ratio changes proportionally to the increase in rpm - the engine has an easier time with the shorter ratio, but this only allows it to spin faster to maintain ground speed. Of course, all bets are off if you are already accelerating. Acceleration may increase with the shorter drive ratio.

There are a few corners at tracks in CA where we apply throttle and lean angle at the same time. This only works on the track because we get to practice those instances over and over and over. I know from prev laps that X amount of throttle works with my tires, suspension, conditions, etc. If I were to take a diff bike out, I'd have to adjust or risk a terrible highside.
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Old 07-12-2021, 08:48 PM   #21
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My take was also missing the line, and adding throttle way too early. At that point on six, you're leaned over way too far to be energetic at all with throttle until you start to get the bike upright, which is doubly hard to do when you are running out of track due to a bad line.

Take away lean angle, add throttle.
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Old 07-13-2021, 04:54 PM   #22
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Originally Posted by stangmx13 View Post
Does it? Ive never been able to fully decide one way or the other. Assuming maintenance throttle, will someone's speed change as lean angle changes? Im leaning towards 'no'. The drive ratio changes proportionally to the increase in rpm - the engine has an easier time with the shorter ratio, but this only allows it to spin faster to maintain ground speed. Of course, all bets are off if you are already accelerating. Acceleration may increase with the shorter drive ratio.

There are a few corners at tracks in CA where we apply throttle and lean angle at the same time. This only works on the track because we get to practice those instances over and over and over. I know from prev laps that X amount of throttle works with my tires, suspension, conditions, etc. If I were to take a diff bike out, I'd have to adjust or risk a terrible highside.
Match the RPM with a dyno curve. RPM increases as the tire's leaned over which can equate to torque falling, depending on what RPM the bike's at. Usually it's more torque as the bike is pushed up to the fatter part of the tire.
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Old 07-14-2021, 12:44 AM   #23
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It depends on where the engine is in the RPM range and how positive the throttle is.
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Old 07-26-2021, 07:27 PM   #24
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If in fact he lost the rear on this one, anyone know whether traction control would’ve caught it? I’ve never ridden anything that had it, so curious about that. Seems like a good idea, on the big bikes anyways.
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Old 07-26-2021, 09:03 PM   #25
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If in fact he lost the rear on this one, anyone know whether traction control would’ve caught it? I’ve never ridden anything that had it, so curious about that. Seems like a good idea, on the big bikes anyways.
TC would very likely have saved this.

Before CSS went to S100RR’s, about 45% of crashes were the result of losing the rear by adding throttle and lean angle simultaneously. With TC, it’s essentially zero.
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Old 07-26-2021, 09:50 PM   #26
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If in fact he lost the rear on this one, anyone know whether traction control would’ve caught it? I’ve never ridden anything that had it, so curious about that. Seems like a good idea, on the big bikes anyways.
TC has given way to the 5/ 6 axis stuff with the bank angle sensors, etc. I'm finding recommending more literbikes to riders I know for track duty due to the safety of all the new rider aids.
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Old 08-09-2021, 07:33 AM   #27
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Really interesting. I know I am chum compared to the track sharks in this thread. However, I have passed (several times) and been passed by Michael Earnest using that same inside line. Thus, I don't think the line is the problem, unless the inside surface is a mess.

Edit: Another review indicates a generous use of the handlebars to turn into the corner to avoid the other bike. This may be where the issue begins. The front starts to go, which lightens the rear and then the rear loses grip. Thus we think it's the rear causing the crash when really it's the turn in on the front.
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