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Old 05-14-2020, 04:00 PM   #1
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Chuckwalla crash hill lowside

A low side going around crash hill, a negative cambered turn, at Chuckwalla. This was during the amateur race session where all you had to do was complete three laps and not crash. I didn't finish two laps

I had initially thought it was a lowside from bad line and less-than-smooth throttle input, but wanted to get others' thoughts on this one. Crash is at 4:15

https://youtu.be/izmZLz-FAdw

Last edited by Maxdb; 05-14-2020 at 04:01 PM..
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Old 05-15-2020, 08:14 AM   #2
Tom G
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Looks like the other front riders knew the track well, you didn't.
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Old 05-15-2020, 08:55 AM   #3
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Looks like the other front riders knew the track well, you didn't.
Yes you're absolutely right, I was definitely new to that track when I went down. I subsequently raced an R3 around the track and know the lines I took in the video are way off..


What I find interesting about this crash is that based on the audio it seems I may have lost traction in the rear when hard parts touched down rather than the other way around.. I had a new engine case cover on the right that looked the business but was very bulky and in retrospect may have limited my ground clearance (I think)
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Old 05-15-2020, 10:07 AM   #4
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NRS school with Trackdaz.. The good ol times.

Crash Corners/Garcias Hill is a slow corner. To me, looks like you tried to throttle hard in the camber section, that is always a recipe for disaster.
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Old 05-15-2020, 10:38 AM   #5
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NRS school with Trackdaz.. The good ol times.

Crash Corners/Garcias Hill is a slow corner. To me, looks like you tried to throttle hard in the camber section, that is always a recipe for disaster.
you can hear that his rpms were constant once his right lean angle was set, and for at least 1 full second before he crashed. at a minimum, his throttle was constant.

given the lean angle addition, his rpms probably should have risen a bit more. this suggests he was using too little throttle and actually slowing unintentionally.
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Old 12-10-2020, 05:51 PM   #6
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Originally Posted by stangmx13 View Post
you can hear that his rpms were constant once his right lean angle was set, and for at least 1 full second before he crashed. at a minimum, his throttle was constant.

given the lean angle addition, his rpms probably should have risen a bit more. this suggests he was using too little throttle and actually slowing unintentionally.
With Rob here on what happened. Rear pivots around the front to the outside. Lost the rear due to levering it per Rob's comment(s).

I'll add: go walk the track and that turn specifically next time. Backing your video up to your first lap, at the point where you hit the ground there's several gouges in the pavement. That's a good clue there's a physical element to the track there. You're very tight to the inside curbing on lap 2. I can't tell if your rear wheel gets near the Grand Canyon between the track surface and the curbing.

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all of the above means its a terrible idea to add more throttle while near the limits of traction. as FourSixThree said, you must first remove lean angle... then you can add throttle. doing so in the opposite order will put you on the ground 9 times out of 10.
And to add to G's and R's great advice: best to make sure the bike's going where you want it to go before taking away lean angle/ adding throttle.
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AFM #6 2020

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Old 05-15-2020, 10:20 AM   #7
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mistake #1: you missed the first left apex, taking it way too early. your flip was also slow-ish. this sent you wide and closed off the line for the right turn, forcing u to accomplish more turning way late. thats really bad for a corner that falls away.

mistake #2: it looks like you added some lean angle right at the top of the hill, the worst possible place.

mistake #3: the extra lean angle and the track camber caused hard parts to scrape.

3 mistakes in one corner almost guarantees a crash.

your throttle control sounds fine.
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Old 05-16-2020, 02:45 PM   #8
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Originally Posted by stangmx13 View Post
mistake #1: you missed the first left apex, taking it way too early. your flip was also slow-ish. this sent you wide and closed off the line for the right turn, forcing u to accomplish more turning way late. thats really bad for a corner that falls away.

mistake #2: it looks like you added some lean angle right at the top of the hill, the worst possible place.

mistake #3: the extra lean angle and the track camber caused hard parts to scrape.

3 mistakes in one corner almost guarantees a crash.

your throttle control sounds fine.

Havenít had such a thorough analysis shared with me before. I think that was spot on. Thank you!
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Old 12-10-2020, 01:10 PM   #9
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Added lean angle late in the corner to correct for an issue with bike placement. This would fall under 'rushing corner entry'. If you had slowed more up the hill, you would have been fine.
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Old 12-16-2020, 11:12 PM   #10
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Don’t beat yourself up too much. I was there late last year and one of the instructors did the same thing at the same spot. Wiped out his Daytona.
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Old 12-20-2020, 09:37 AM   #11
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Add lean angle, take away throttle.

Take away lean angle, add throttle.
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Old 12-20-2020, 12:09 PM   #12
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If it's any consolation, that exact spot is the only place I've crashed on that track on my S1000R. That's why I run my rearsets nice and high now.

I did the same as you- turned in a bit too late on the left, which set me up wrong for the off-camber right. As Dammy pointed out above, the key to the complex is getting that apex on the intro left correct and letting the right and second left sort themselves out naturally.
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Old 05-15-2020, 08:07 PM   #13
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Not enough throttle. That's my opinion. So you were at max lean and just fell over. Hitting the berm didn't help either, because doing so momentarily upset the weight balance.

Not a racer but I did watch your video twice to try to understand.
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Old 05-16-2020, 06:58 PM   #14
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Not enough throttle. That's my opinion. So you were at max lean and just fell over. Hitting the berm didn't help either, because doing so momentarily upset the weight balance.

Not a racer but I did watch your video twice to try to understand.
I too stayed at a holiday inn one time
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Old 05-17-2020, 08:38 AM   #15
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As Stangmx pointed out, this crash started when you turned in too early for the previous corner which gave you poor track position entering the right hander.


You can see in the video that there are lots of cones in the corners, those cones are there to give you specific information about where you bike should be positioned on the track, and this is the key part: The cones also tell you what direction the bike should be pointed at that specific moment.

If you stop the video at 4:13 you can see two apex cones on the left side of the track. If you have your bike close to the cones with your knee over the curb you will apex the corner in the right place. If you also have your bike parallel to the two cones, then your bike will be pointed in the right direction while at that apex. (Parallel means that your front tire and back tire are the same distance from the two cones when you are beside them)

This proper bike placement would have resulted in the bike pointed the right direction for a safer entry into the right hander.

It sounds like you had hard parts hit the ground before you lost grip, but even with more ground clearance your current bike placement will still result in that same crash in that same corner, maybe not at your current speed, but as soon as you tried to go even a tiny bit faster, that bike placement will exceed the limits of the tire.

At 2:13 the rider in front of you does exactly the same thing. You can clearly see that he apexes the corner way before the two cones and he is nowhere near parallel to the cones as he goes by them. (Front wheel is further away from front cone that back wheel from back cone). This results in lots of risk and being way wide of the cones at 2:17 and again at 2:20. At 2:20 you can see that he is adding lean after the cones while trying to accelerate onto the straight, which has all the ingredients for a highside.
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