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Old 03-01-2018, 10:14 AM   #31
thasmydjay
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Originally Posted by raymond_h2002 View Post
Hey DJ! I pitted next to you in the garage during the weekend; it was nice meeting you! I saw you rolling in after you got picked up after the crash and wanted to chat with you more, but I thought it was best to give you your space. Glad you're seeking out advice here!

Something that's popularly discussed in motorsports is the traction circle, which you may want to google to read up on / watch videos. The ELI5 explanation is basically that you have vertical forces, which are accelerating and braking, and lateral, which turning left and right. For a given radius, as you're increasing the forces in one axis, you gotta let up on the other. Example, if you're braking and entering a turn, you gotta let off the brakes as you turn in... when you drive out, you gotta let off the turn as you throttle out.

I jumped around your 2nd video a bit and noticed that you were throttling in some places that could have gotten you into trouble, notably on turn-ins in 8 / esses. My heart stopped for a few seconds here and there, as a few of those moments could have potentially led to a crash.

The pace dictates the margin for error, and so when you start going faster you have less room for mistakes. My advice is to slow down and work on fundamentals like when to brake, when to accelerate, and how smoothly you go about doing each. From what i've seen, those areas need some refinement for the pace you are trying to carry. It sucks to hear this because you see other people going faster and it's easy to think, man, I can do what they're doing and probably more! That's what was going through my head when I started breaking out of C-group and into B. Riders in A group aren't faster just because they're twisting the throttle and grabbing the brakes harder... it's all the in-between nuances that support their consistency and create the opportunity for speed. It's important to develop technique that is scaleable in a safe manner.

Hope to see you soon!
Raymond! Nice meeting you too man, I appreciate the feedback. I will definitely look into that concept and approach my riding differently after all the information on this thread.
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Old 03-01-2018, 11:00 AM   #32
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So would the reason why I would not want to add throttle and lean angle at the same time would be because if I do so, it takes away contact patch and causes me to lose the front? Which is what happened during my crash along with the tires/suspension/track being cold?

However, maintenance throttle or trail braking causes a consistent contact patch while turning in?
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Old 03-01-2018, 11:01 AM   #33
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funny story... every time ive tucked the front in the past 2 years, i was off the brakes. yet on later laps, id go through that same corner faster while still holding the brakes and not crash.
I don't think I have ever crashed a bike on the brakes and trailing into a corner. I certainly have off the brakes and into a corner.
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Old 03-01-2018, 11:47 AM   #34
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So would the reason why I would not want to add throttle and lean angle at the same time would be because if I do so, it takes away contact patch and causes me to lose the front? Which is what happened during my crash along with the tires/suspension/track being cold?

However, maintenance throttle or trail braking causes a consistent contact patch while turning in?
The more common issue with adding lean angle and throttle at the same time is sliding the rear. Both adding lean and adding throttle increase the demand for traction at the rear. Doing both at the same time makes the demand increase faster and if you have a slide, it's harder to tell what caused it.

Also, being on the gas stabilizes the bike. A stable bike is harder to steer; not what you want at the turn entry.
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Old 03-01-2018, 12:01 PM   #35
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So would the reason why I would not want to add throttle and lean angle at the same time would be because if I do so, it takes away contact patch and causes me to lose the front? Which is what happened during my crash along with the tires/suspension/track being cold?

However, maintenance throttle or trail braking causes a consistent contact patch while turning in?
pretty much

from a conceptual level, we try not to add throttle and lean angle at the same time for two reason.
1. because its too many changes at the same time to predict the outcome.
2. because its usually the slow way around the track.
so its risky and slow, giving us no reason to do it*

from a technical level, acceleration can shift weight rearwards and reduce the contact patch. but a lot of that depends on the setup of the moto and how much acceleration. its very hard to say technically what happened in your crash.

the cool thing about riding at maintenance throttle or while trail braking is that there are fewer unknowns. at maintenance throttle, the contact patch doesn't shrink add lean angle, it grows a tiny bit. and if u do it slow enough, u get feedback in the bars and could catch a slide. while trail braking, you are controlling the size of the contact patch with the front brake and we know that it must be larger than at maintenance throttle. all those knowns are good things too, which is y these are great tools for riding around a track.

*ive been to 10 tracks and can think of 1 or 2 spots where I add throttle and lean angle at the same time. both of them are a slower corner that leads directly into a faster corner. for ex, T2 at Fontana. T1 is an ess that ends with a right, leading directly into the left T2. T1 is slower and I know I can go full throttle in 4th or 5th through T2 on a 600. so I smoothly go WOT while putting the bike on my left knee. since its so fast, maintenance throttle is prob at least 60% throttle. so adding that extra throttle isnt too much more power. but I def didnt do that the first few sessions around that track . liter bikes do high side here thanks to what tzrider just said above ^^.
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Old 03-01-2018, 12:58 PM   #36
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Robert / stangmx13 -

Thanks for the updated info on the traction circle!

Regarding throttle/lean angle being added at the same time in very few places, would you also do it at the transition from exiting 11 into 12/13 at Thill? I'm terribly slow coming out onto the back straight and a lot of it I think comes from being timid about getting on the gas sooner.

-Raymond
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Old 03-01-2018, 01:12 PM   #37
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Im not sure. it does seem like ud need to into T12. but I don't have enough laps around Thill to know off hand. im sure other ppl in this thread could tell u what they do.
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Old 03-01-2018, 03:22 PM   #38
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Robert / stangmx13 -

Thanks for the updated info on the traction circle!

Regarding throttle/lean angle being added at the same time in very few places, would you also do it at the transition from exiting 11 into 12/13 at Thill? I'm terribly slow coming out onto the back straight and a lot of it I think comes from being timid about getting on the gas sooner.

-Raymond
Ideally you'd start to stand up from T11, rolling into the throttle hard when you are pointed properly, back off and turn into T12 maintaining throttle, and then start winding on just past the apex of T13 and carry the drive to the edge of the track. I get the front end into the air exiting T11 if I am hurrying. I don't add throttle and lean angle simultaneously. Here's a hint: T13 is an exit corner. It's all about getting the best exit, which means apexing T13 and getting the bike upright asap while rolling into the gas. You need to use ALL the track to do this. If that's not clear, the exit at T13 is where you start to pick the bike up, at that point you start to roll the throttle on. That's the best way to remember when to roll on. As you begin to take away lean angle you begin to roll on throttle. The bike doesn't have to be upright to get it pinned, not at all. It just has to be off the edge of the tire. That's the danger zone. Watch MotoGP, you'll see this time after time, start roll, pick up bike a bit and then smoothly roll into full throttle, if that's the exit that has room.
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Old 03-02-2018, 08:43 AM   #39
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Thanks for your advice Ernie!

Sorry DJ for hijacking this thread; back to Sonoma discussion
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Old 03-02-2018, 10:21 AM   #40
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Thanks for your advice Ernie!

Sorry DJ for hijacking this thread; back to Sonoma discussion


I reread my description, it's not great. The rolloff of throttle entering T12 is not a shutoff, it's just a slight rolloff. Once you get into the throttle standing up from T11, you are in it all the way to the bridge.
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Old 03-02-2018, 11:33 AM   #41
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rolling back to maintenance throttle is def a skill we all should get good at
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Old 03-12-2018, 06:13 AM   #42
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Sonoma is technical AF! I low-sided on T2-3, and I attributed it to cold tires. I'll get some lessons next time I'm out. Makes a HUGE difference.
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