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Old 03-08-2021, 11:29 PM   #1
self_moto
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Lowside Sonoma 3a

Hi,

On season opener at Sonoma (02/20) had a "misfortune" to lowside in 3a. Totally understand that's my fault, but would like some clarification. It was freaking cold that day (60s), it was 11am session, 4th lap.

My understanding of situation - lost front, mostly because carrying too much lean angle over the crest, my line was off - by the time right before the crash I should've started picking up the bike already.

What do you think?

Thanks!


youtu.be/BJG097vIf-I
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Old 03-09-2021, 08:31 AM   #2
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Sorry about your crash. That's 3B by the way
Only thing I can see is you were wide at the apex. The pavement starts to drop away there.

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Old 03-09-2021, 11:38 AM   #3
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I would have liked to accomplish a lot of that right turning much sooner. That way when the pavement falls away, you aren't asking for as much grip from both tires. You were little wide out of 3A and were late & slow with your direction change. This put you really close to the 3B curb, essentially the worst spot to be in. The easiest way to fix this will be to slow more for 3A.

On cold days, you really need to use the brakes to keep heat in the front tire. The front tire sits in the wind and gets cold constantly. The more you can do to keep heat in it, the better your day will go. It seems like you could have slowed much later for T3 and used more front brake and less engine braking.
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Old 03-09-2021, 08:01 PM   #4
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As Robert says, your wide exit from 3 made you low line 3a and forced you to keep too much lean angle over the crest. I’d leave it leaned over a little longer in 3, which will set you up for a later apex in 3a. You should be picking up lean angle and back on the gas about where you lowsided.
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Old 03-10-2021, 11:15 AM   #5
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Agreed - compromise 3 to get a better entry and preserve lean angle through 3a (btw it is 3 and 3a, not 3a and 3b). And a more aggressive steering input to get bike leaned quicker.
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Old 03-10-2021, 06:18 PM   #6
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From what I can hear, you're lightly off the throttle going up the hill to 3b and then, off the throttle completely after turn in all the way until you lose the front. 3b will do that to you, off throttle. I'm guessing that is how you were dealing with running wide.

I agree with the guys above that the line choice set you up for your decision to cut throttle, but I don't agree that you can't make the corner just fine with a shallow (right side) entry. You just have to turn a bit sooner (if you're going to keep speed up). 3b is one of my best outside passes on that track. It's epic and undefendable. The key is keeping the throttle open a bit and using the camber of the rear tire to help transition and steer the bike.

My conclusion: chopped throttle at wrong place and for too long.

Hope you're doing ok. The track looks horrible BTW.
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Last edited by Holeshot; 03-10-2021 at 06:21 PM..
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Old 03-10-2021, 07:02 PM   #7
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You're right that he could maintain the low line. Turning a little later into 3a (right-hander) would also solve the problem of being forced to keep it leaned over and off the gas over the crest.
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Old 03-10-2021, 07:08 PM   #8
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The track looks horrible BTW.
I thought the rumor was Sonoma was getting a repave this season. Maybe covid pushed that back...
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Old 03-11-2021, 08:14 AM   #9
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I thought the rumor was Sonoma was getting a repave this season. Maybe covid pushed that back...
I remember hearing that in January of 2019 too....
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Old 03-11-2021, 09:11 AM   #10
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Thanks for feedback everyone, very helpful! Definitely a lot of things I need to address...
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Old 03-18-2021, 06:58 AM   #11
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I'd suggest being a little wider on entry and using a tiny bit of trail braking to keep that front tire planted.
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Old 03-23-2021, 01:51 PM   #12
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I crashed there season opener 2020 with ptt. Same deal. Cold tire, early turn in, too much lean angle. I ended up fixing it up and getting back out after lunch and the Sunday. I got a lot of pointers from some of the instructors (seasoned racers) and they all said a combination of what everyone else is saying. Carry 3a radius a tad bit later to start to stand the bike up over 3b. Glad you're alright and will live to ride another day!
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Old 03-23-2021, 02:44 PM   #13
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You're right that he could maintain the low line. Turning a little later into 3a (right-hander) would also solve the problem of being forced to keep it leaned over and off the gas over the crest.
Totally agree. Once you realize you've made a mistake (turned in too early) though, you've got to recognize what the mistake is, what the effect will be, and how to compensate so you don't become the accident...all before you reach the crash point!

That's "experience" in the Moto world, in a nutshell.
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Old 04-07-2021, 04:30 PM   #14
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I watched that video a bunch of times and I think the bike was already on the ground before he crested the hill. Just asked too much from the front tire. When you screw the pooch at the bottom of T3 and run wide and then flick it right and end up with an early apex to 3A, you can't make up for that with a bunch of extra lean angle. You have to stay off the throttle and maybe even brake a little and hope there's enough track out there to keep you out of the dirt. Adding a ton of lean angle just turns one mistake into an even bigger mistake.
And thanks for posting that video. Great teaching opportunity.
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Old 04-10-2021, 06:48 PM   #15
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If I’m “reading” this video correctly you were not on the brake as you tried to make that turn. I don’t brake there either, but a bit of brake would have helped keep the front planted and make the turn with the line you had. Better to fix the line as others mentioned, but if I were going in on your line I’d probably want a finger brushing on the brake to steer through the turn.
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