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Discussion Starter · #1 · (Edited)
Hey guys ...

Here's my crash videos from a few days ago. Coincidentally crashed twice in this corner on that day.

First crash:

The first one happened at the end of the first session in the morning. I originally attributed it to cold pavement, though after watching the video there's definitely more to it.

Second crash:

Second crash was at the end of the last session in the day. 4-5 minutes on the board left so I figure I could do another 2 lap before packing up. Tires and pavement was definitely already warm.

Not very evident in either video, but the tail was wagging both time before I went down. This corner is an blind left uphill braking corner following the fastest section of the track, so I down shifted both time ( though originally thought I didn't downshift on the second crash ).

I watched the video quite a few times and still haven't figure out all the reasons why I crashed. With both crash, it was most likely the ugly downshift which started the wag JUST before turn in.

With the first crash, seems like the wag settled a bit then started again when I turned in .. perhaps I 'flicked' my turned in too hard attempting to keep up with the red tail gixxer in front ?

With the second crash .. I wasn't spooked so much by the inside pass ( yellow bike ) as mush as I was spooked by the wag since that's what caused crash 1 .. I > think < I tried to straight out the turn to give the bike time to settle .. then I realized that I was running out of pavement and couldn't get the bike settled before turn in .. panicked .. held on to the bars for dear life ( death grip ) which made the wag worse .. then probably some target fixation happened in there.

What else did I miss ? Pretty sure there are plenty.
 

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I'm no road racer, but in the first video the downshifts at :27 and :31 were pretty harsh. That may have upset the traction enough to cause your rear end to get squirrely before your turn in. You hear some tire squeal at both downshifts. If you had a slipper clutch, you might get away with it.
 

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Discussion Starter · #4 ·
Track isn't that bumpy .. its me that is bumpy / rough / unsmooth .. =)

The inside berm on that turn is raised like about 1" but I don't think that played a part in my crash.
 

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Try to be more smooth with your shifting and body positioning from 1 side to the other so you dont upset the bike so much get with a CR and have them follow to see what is up ! Remember you have to go slow to learn how to be fast !
 

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The first one . . . I really dont know. From the sounds, Im guessing locked up rear, while leaning or something.... But really tough to say.

Second one, still looks like you got spooked by the other rider on your left.

Moving forward, work on your lines. You're staying way away from the apex. You need that line to be right so your corner exits dont put you in the dirt.
 

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The second video looks like you just failed to tip it in, were you getting head shake there too? You should have turned in much earlier there

The outside of the track is dirty and you gain grip from the rubber that's laid down on the inside.
 

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Discussion Starter · #9 ·
I don't remember head shakes but perhaps because I was more focus on the tail wagging.

I think I can try to practice smoothing out my inputs ( shift / changing body positions ) and getting it done earlier in the process to reduce the chance of a tail wag at turn in point.

However, if it does happen again, what is the best way to stabilize it ? Clutch in ?
 

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Now this is going to be a extreme case of 'Pot calling the kettle black,' but your lines are all over the place, and usually far from ideal. Were there any control riders you could've asked to follow to get a feel for the proper lines on the course?
You were wide/off on a lot of turns, which doesn't give you much room to maneuver when things go south. It also sounds like your downshifting is pretty rough... not sure how much you've ridden on a track before, but it was recommended to me to just kinda stick to one or two gears until I was comfortable with the track and could get my lines down. That aside, since our engines have so much engine braking, one really needs to let out the clutch smoothly and evenly when you're downshifting at those speeds. Don't worry too much about excess wear from slipping; the oil bath helps keep it cool. Besides, changing out the clutch plates on a motorcycle isn't nearly as difficult or time consuming as on a car. :)

Your tank sure got the hell beat out of it! Are your forks and such still straight?
 

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Discussion Starter · #11 ·
Actually this was a 2 day novice school ( my second one ) so I've been working with CR / instructors all day long. I guess its just me who's dense and isn't absorbing their teaching very well.

In the second video, the red bike passing me was an instructor that I just rode with for the last 3-4 laps working on body positioning. He flagged me down because certain corners of the track I had the bike at basically max lean angle using pretty much all the tire and needed to get off the bike more to stand the bike back up, otherwise I would .. guess what .. crash.

The previous session, I also worked with another instructor ( on an SV superbike ) who was trying to teach me to downshift smoother by blipping my downshift instead of doing the "Pridmore downshift" .. but supposedly my lines were 'fine'.
 

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Might just be the camera angle I see, then - as well as my lack of experience. :)

Body positioning is hard for me as well. I think 'aw yea I'm hangin off so much,' then I see in a picture it looks like my knee is about three inches away from the body and I've got a sliver of asscheek off the seat. :(

To me, personally, the 'Pridmore' way of shifting (had to look that one up) seems the most forgiving and easy way to do it, if not the fastest.


Live and learn, they say. I have a feeling if I want to get faster at my next track day, I'm going to have to go outside my comfort zone and wind up in the weeds. Hopefully it'll be a nice, gentle low-side and the bike doesn't snag somewhere and start flipping and tossing about, leaving me with a shattered and broken husk of aluminum, steel, and plastic.
 

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First off, Glad you're ok. As far as why you went down and how to avoid a repeat performance, it's pretty clear to me that the biggest problem was with the rear tire loosing traction the downshift. I struggled with this quite a bit as I started track riding last year, and I had a couple close calls because of it. I'm no expert either, but since no one else has added much of any specifics, here are a few bullet points on what helped me improve on my corner entries.

1 rev match downshifts. with the engine braking of the sv and no slipper clutch it's a must. otherwise there is just too much force on the rear tire when it has very little weight left on it due to deccelleration from braking. You will want to learn how to rev match the engine to the next gear while still braking. This will keep your hand really really busy but it's the smoothest method when done right, and even if you're off a little bit it won't end up as bad as if you didn't rev match.

2 get the downshift out of the way earlier. this way if the rear brakes loose you can hold off on tipping in until it settles down. If you make a rough shift any other time than straight up you're in trouble.

3 suspension. i found that i had far too little sag in the rear end which caused the suspension to top out and reduce grip significantly or sometimes even chatter and hop.

4 rear brake. just don't even touch it. with the ammount of braking force the engine is already putting on the wheel there is very little traction left to use anyway so most of the time i tried to use it i just locked it up. I'm not nearly good enough to be backing it in or anything like that yet so i just leave it alone



again, I'm no expert, so If you don't like my advice.... well darn. If any really skilled guys want to expand or correct on this I'm all for it
 

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ummm, suspension, hello!!

do you have any suspension?? more than a 'Gxxr' shock or a '636' shock??

and while you are a bit hamfisted*, looks like suspension AND hamfistedness on the side...lol









*heavy hands, not very smooth, pounding...and probably getting some arm pump from holding on too tight!!
 

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9r.. i'm with ya till #4...as you really have to try to lock up a stock SV rear, if you cheat/trail the rear on corner entry it WILL settle the chassis and cut a nice line thru the exit...
 

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Discussion Starter · #16 ·
Haha .. yeah I guess you're right .. it seems I'm hamfisted and need to learn to be smoother.

What is the best method to do so ? Back to parking lot practice figure 8 to practice throttle control ?
 

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Discussion Starter · #17 ·
Also, is there an RPM point where it would be a bad idea to shift even with rev match ?

For example if I'm in 6th at 8.5k to 9k RPM in a fast straight and I need to if I kick down to 5th .. I assume the engine would be at 9.5k to 10k rpm .. which is borderline red line.

In this situation, should I brake first and get the speed / RPM down before I start the downshift ?
 

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Glad you are OK. Who exactly was running this track day? I've never seen a novice group where passing was allowed on the inside. And, whoever told you your lines were fine or that you shouldn't shift like Pridmore should be fired. I've also never ridden with an organization that allows you to get back on the track after you crashed once.

You crashed at the same corner because it presents the same challenge. It's a high speed straight that leads into a low speed corner. You have a lot of stuff to do in that situation: (1) you need to slow down; (2) you need to mental and physically set your lines; and, (3) you have to change your body position. These things pretty much have to occur simultaneously and in advance of the corner. Otherwise, you'll upset the suspension and, well, you know what happens after that.

In the first video, it looks like you were starting to adjust your body position when the bike hopped the first time. This freaked you out, and you got back in the center of the bike, then downshifted again and upset the suspension again. You were way out of position and simply ran off.

So, it looks to me as if the primary cause was that you didn't rev match and you got the rear tire hopping. That started a chain of events that lead to the crash. There are two cures for hopping: (1) practice rev matching on every shift; (2) get a slipper, aka, anti-hopping clutch.

Lesson #1: Rev Match. Rev matching upshifts is easier, but you should still use these shifts to practice being smooth. Pull the clutch in smoothly, and let it out smoothly. The goal is to keep the suspension neutral. If the front dives, or the rear starts hopping about, you need more practice. You may also want to have someone who knows bikes ride yours to make sure that the clutch is functioning properly and not grabbing. You should also may someone look at the suspension to make sure its right for you. You look like a big guy and the stock SV suspension is set up for lightweights.

Your lines. You are not hugging the inside apex. Watch a motorcycle race: AMA, WSBK. MotoGP it doesn't matter. They all hug the inside apex. Why? To block people from passing on the inside. Look at the last few seconds of your second video. You are way outside. You are so far outside, the guy on the yellow bike who's trying to pass you, can't pass you on the outside, so he passes you on the inside. Then he apparently realizes he's breaking the rules and parks it on the corner - blocking your entry.

So, it looks to me like not only did you mess up the downshift on the second crash, but when you looked to turn in, you saw the other bike already there, so you stood the bike up and ran off.

Lesson #2: Always block your inside line. That prevents your entry from getting blocked, and more importantly, keeps someone from taking you out. http://www.ducativalentinorossi.com/Valentino_Rossi_Takes_Out_Stoner.html

If you really want to see how smoothly (and quickly) a bike can be shifted, do a class with one of the Pridmores and do a two up ride. You'll also pick up a lot of go fast tips. Good luck.
 

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Also, is there an RPM point where it would be a bad idea to shift even with rev match ?

For example if I'm in 6th at 8.5k to 9k RPM in a fast straight and I need to if I kick down to 5th .. I assume the engine would be at 9.5k to 10k rpm .. which is borderline red line.

In this situation, should I brake first and get the speed / RPM down before I start the downshift ?
Yes and yes.

The whole braking process should be: roll off the throttle (don't slam it shut), and as you are rolling off the throttle, you roll on the front brake (you may add some rear brake as you get more comfortable, but the SV's engine braking helps stretch out the chassis like dragging the rear brake does) then downshift. Smoothly pull the clutch in, and most importantly, smoothly let the clutch out. In a perfect world, you shouldn't feel a thing.

While you're doing the above, you're also going to be thinking of your position on the track, and positioning your body. You should have all this done before you tip in. You can experiment with trail braking and shifting your weight while in the turn after you get comfortable with the basics.

Also, when you get a chance, practice adjusting your line with your throttle. If you give a little throttle, you'll push wider. If you ease off the throttle, you can tighten your line. Again, practice being smooth. Slapping the throttle on or off does bad things. Good luck.
 

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Make sure you are done adjusting your body position BEFORE you tip your bike into the corner. You shifted your weight around a massive amount right before the first crash which will take your suspension outside of the optimal movement zone, which is right in the middle. When that happens your bike will not be able to lean as much, and your tire wil 'hop' on the pavement.

Although your body position is not visible in the second video I suspect that also contributed to that crash as well. That pass on the inside is suspect for novice riders for just this reason; you end up turning to late and to wide.

You really need to educate yourself on some racing techniques. While there are many contradiction opinions on why you crashed, because most people arn't experienced racers, you brake some fundamental 'good' techniques what will be evident when you educate yourself.

I recommend starting with this book:

[ame]http://www.amazon.com/Twist-Wrist-Basics-High-Performance-Motorcycle/dp/0965045021/ref=sr_1_1?ie=UTF8&qid=1341080084&sr=8-1&keywords=keith+code[/ame]

It will save you a lot of money in the long run. Keep racing and keep having fun!
 
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