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Old 04-30-2017, 05:56 AM   #16
RV6John
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Originally Posted by Pierre I am View Post
for the experts: why did this scenario translate into a highside vs a lowside?
I don't claim to be an expert but a highside is usually proceeded by a loss of rear traction and the back of the bike starts to come around (oversteer). You can tell that is happening in the video as the handlebars are turning into the skid.

If traction is never regained, it continues to yaw and you have a lowside. Unfortunately, the source of the lost traction, excess throttle or brake, is frequently reduced sharply, and the rear regains traction. Now you have a bike going sideways at speed with a big weight (the rider) at the top and it will be a highside.

Loss of traction in the front has the bars turning into the turn and will result in a lowside although I'm sure someone has managed to turn on into a highside at some point.

Compare what happens to the handlebars on this front loss low side to the OPs vid.


youtu.be/4k5ocXPVqqI

I'll agree with others points. I think the other bike passing on inside threw off you rhythm, you were not aggressively on the throttle on the other corners and I did not hear it just before the crash.

My guess is that you were watching the other rider too much, doubted your corner entry speed and went for the rear brake.

As I have been told many times, the rear brake is pretty useless on the track unless you go off the track. Yes, the track ninjas use it to settle the bike in the turns, but I ain't there yet

Heal up quick and thanks for sharing the vid.
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Old 05-01-2017, 04:40 PM   #17
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Moved from B+ to A group right before lunch. Didn't take a break between sessions. High sided on turn 10. I'm thinking I accidentally locked the rear brakes on entry...
What was your criteria to move to A, if you aren't even sure if you locked the rear brake on entry? I might suggest that perhaps B+ was more than adequate for your skill level. Even in B, you should know whether you are using your brakes or not.

I can't tell exactly where your rear wheel is located, but there is patch out there from the autos, and that patch has less grip than the regular asphalt.

Regardless, your line was nothing like the rider that passed you. You should have been farther outside and started the turn much later. You were already leaned more than the other rider BEFORE the apex. A good exercise to improve your track cornering and speed is to try to end a turn as close to the inside as possible. This will force you to start your turn-in later. This will also train you to make safer passes on corner exit, rather than trying to beat people to the inside of the corner on the brakes.
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Old 05-02-2017, 03:31 PM   #18
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Originally Posted by clutchslip View Post
What was your criteria to move to A, if you aren't even sure if you locked the rear brake on entry? I might suggest that perhaps B+ was more than adequate for your skill level. Even in B, you should know whether you are using your brakes or not.

I can't tell exactly where your rear wheel is located, but there is patch out there from the autos, and that patch has less grip than the regular asphalt.

Regardless, your line was nothing like the rider that passed you. You should have been farther outside and started the turn much later. You were already leaned more than the other rider BEFORE the apex. A good exercise to improve your track cornering and speed is to try to end a turn as close to the inside as possible. This will force you to start your turn-in later. This will also train you to make safer passes on corner exit, rather than trying to beat people to the inside of the corner on the brakes.
I see your point. I kept hitting traffic in B+ and thought following faster riders would help improve line selection and my general form.

I'm still not sure if it was rear brakes or throttle. Before the crash, I was having this strange issue with accidentally applying a small amount of throttle while on the front brakes. This caused the rear end to wag a little bit. I'm thinking it had to do with me not being used to the deadzone on the throttle if that's a thing...It was a first for me but that might have caused it too.

This also wasn't my bike

I wish I could remember more from the crash. At any rate, I appreciate the perspective and advice from everyone. My shoulder has already made huge gains in a weeks time, I'm hoping to be back on my bikes within the next two months.

Last edited by MegaMatt; 05-02-2017 at 03:32 PM..
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Old 05-03-2017, 11:52 AM   #19
RV6John
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Originally Posted by MegaMatt View Post
This also wasn't my bike
I'm guessing that it not being a familiar bike to you was also a significant factor.

Most fuel injected bikes have slight dead area just off idle due to fuel cut on deceleration for emissions.

With some bikes, it is not noticeable, some don't handle it so well. The most recent example is when Yamaha rolled out the FZ-09 a couple of years ago.

Glad you are doing better.
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Old 05-03-2017, 09:44 PM   #20
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I don't know the T-Hill expansion, but you have some issues. You miss the apex of the right at 1:20. You're way off line on the right at 1:25 when you got passed. The fast guy pulls away exiting the turn because proper line. He hits the apex on the left, which you don't, at 1:28. You don't make the left side transition well, your body's crossed up for the last left. Seems like you're trying to close the gap, but you're off line, too fast, and then looks like you tried to apex early. Maybe you hit the rear brake then. Possibly you could have braked deeper, and trail braked to make the turn. The fast guy would have been in a different zip code by then. You can't catch a rabbit until you know the trail.

I got vetted by a control rider before I moved up to A. I still managed to crash my second session because I changed my lap too much.

You can get PTSD after a crash, not in a lifelong thousand-yard stare way, but in a limited way lasting a few months where you sorta obsess about the crash. Hope you heal up, physically and mentally, dust yourself off and move on. Maybe B group.

Last edited by Snaggy; 05-03-2017 at 10:10 PM..
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Old 05-06-2017, 04:15 PM   #21
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Originally Posted by MegaMatt View Post
Cant type much with one hand, but I will say that it was probably a mistake trying to follow a faster rider on a new line at a higher speed than I'm used to through that corner. I normally take a wider line and enter a bit slower. You can kind of see it at the beginning of the clip.
I see a few things Matt:

- RPM's are really low on corner entry (this wasn't the only turn for that). Higher RPM is less intertia/ potential to spin the tire.

- Your line is not the same as rider in front of you. You turned in earlier than them and because of that, have to carry more lean angle and will be pointed the wrong way (not down the track like you need to be) at the same point in the turn as the rider in front of you (IOW, you'll still need lean angle when they will not)

- There's a fairly long skid mark about where you fell. You fell highside which on corner entry is almost always due to two things: RPM too low/ motorspeed to low (siezed motor, no rev matching/ rear tire dragging slower than front) and rear brake engaged while leaned over.

- Your right hand looks to pull the outside bar which is a natural reaction in a slide. However, you really want to put weight on the outside peg instead. Pulling a bar is NOT the same as putting weight in an area. This is why I constantly comment that "push left/ got left" and using bar input to control a motorcycle is not a good primary control. Using legs/ body gives much more leeway for the bike to do what it needs to do.

- The front tire steers right, away from the corner in the video which means the back is coming around the front to the right side.

- You are pitched off the bike to the high side when the steering hits full lock.




somehow, you lost rear traction I think. Once that happened, because you must be riding your bike using high bar effort, you were unable to correct the bar input action and essentialy, put yourself on the ground. Using your body to perform the majority of steering inputs/ control for the lean angle change, you have much more feel for the front end and less input. When the front or rear slides, you're able to control things more easily. It's not perfect, but bar input is BAD thing when trying to ride at the limit, etc.

Many will argue with me, but then again I've never put the bike on the ground due to bar input. Now, Michelin front tires....lots of front end crashes on them...

BTW: your bike may be insurance totaled, but by a racing standard, she's fine. She's a www.ebay.com shopper now, for parts.

Last edited by Holeshot; 05-06-2017 at 04:23 PM..
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Old 05-29-2017, 09:27 PM   #22
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What I saw there was the OP being passed by a faster rider and deciding to step up his pace immediately. Including braking less to carry more speed. It didn't work.
That is what I thought too. It can be sooo difficult to keep your cool when being passed by a faster rider. It is very easy to get towed into a corner you are just not prepared to make.

Bummed you broke your collarbone, but glad you were not hurt worse.
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Old 07-26-2017, 05:57 PM   #23
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Wow....I've got A LOT to learn. I was just introduced to this corner at Keith Code. This was also my first intro to track road racing. I progressed into the low 1:41's and really started to feel comfortable. In the 5th and last session of the one day school, an "experienced" rider passed me on a GSXR750. I decided to try and hang with him, as long as I felt comfortable. I was able to maintain a nice 75 yard "watching" margin.

My instructor (in the lead follow exercise) taught me crest the brow after T8 fairly close to the inside curb (1-2ft). This, I was instructed, would allow for greater exit room (more asphalt) to the left, and therefore greater margin. I watched the GSXR dude crest about 10 feet from the inside, and at our velocity, this carried him almost to the outside edge of the track. He managed to enter turn 9 (albeit deep), but as he leaned the bike (in the marbles to my recollection), I witnessed him violently pile drive the handlebars downward into the asphalt. He hit so hard that there is a deep gash about 12" long in the middle/back of the corner now. He didn't lose the rear. It looked to me as if he tugged too hard at the critical moment on the front brake.
I didn't find out if he dinged his head hard enough to manage a concussion, but he certainly could have from the looks of it. He did separate his right shoulder.
Anyway, I'm not certain that my experience lends constructively to this discussion, but I will try to learn from both unfortunate experiences.
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