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Old 04-05-2018, 08:25 PM   #16
afm199
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A gear to low? Sometimes I wonder what gear to take going into a corner also. Are you implying itís better to get the RPM down and be in a higher gear? Iím still slow, but usually try to have the RPM in the higher range when entering a corner. Am I doing it wrong? Thanks.
The general rule for the gear you enter a corner with is that is the one that gives you the best drive out. The downshift slows you down, but it's not what it's intended to do. You downshift to the gear that puts you in the power band as you are taking away lean angle and rolling the throttle on.

It's not true for every corner, just almost all of them.
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Old 04-05-2018, 09:16 PM   #17
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Originally Posted by afm199 View Post
The general rule for the gear you enter a corner with is that is the one that gives you the best drive out. The downshift slows you down, but it's not what it's intended to do. You downshift to the gear that puts you in the power band as you are taking away lean angle and rolling the throttle on.

It's not true for every corner, just almost all of them.
That’s a good way to explain it. Was just curious, because I’ve watched many fast rider’s videos riding 1000cc bikes around Thunder Hill and some seem to take corners at 5-6k RPM. Looked like OP RPM was around 6k when accident happened. Was that too low / high for that corner?

Last edited by jmann; 04-05-2018 at 09:28 PM..
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Old 04-05-2018, 09:42 PM   #18
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It looks like your turn in rate was little slow which caused you to miss the "first" apex"(we can get into the whole is turn 2 1 turn or 2 turns argument later)
I would start listing to all the Ken Hill pop casts and you will get a lot of great information from them. Might just be me but looked like you were a gear to low, looking at the Rev counter. What gear were you in?
Ken/YCRA talk a LOT about 100 points of grip I would rather take that conversation off thread as it is not directly germane to this discussion

It is great that you are trying to learn from your mistake, that shows a level of maturity that a lot of track riders dont have. Video means no where to hide
I was in 3rd gear, revs between 7-8k when I went on the throttle again.

My mistakes/crashes have taught me the best lessons so far so I am trying to take in as much as I can when that happens (hopefully I won't make a habit out of this). The way I see it, there is always going to be someone more experienced, faster, smoother etc that can teach me a few things, so I plan to listen :-) Thanks for the pointer about Ken's podcasts, will definitely listen to those.
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Old 04-06-2018, 06:51 AM   #19
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A gear to low? Sometimes I wonder what gear to take going into a corner also. Are you implying itís better to get the RPM down and be in a higher gear? Iím still slow, but usually try to have the RPM in the higher range when entering a corner. Am I doing it wrong? Thanks.
I felt your RPM were to low but that is just a personal observation
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Old 04-06-2018, 09:31 AM   #20
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I felt your RPM were to low but that is just a personal observation
Youíre confusing me here. LOL. 😂. Initially you said OP gear was too low. Meaning he should of shifted up 1. Now you said his RPM too low, so he should of shifted down 1. Which one is it? OP states he was in 3rd doing 7-8k RPM. Iíd assume he should of been in 2nd doing 8-9k RPM. Does higher RPM make the bike handle better or easier to get around corners or does RPM not matter at all?
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Old 04-06-2018, 09:37 AM   #21
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You’re confusing me here. LOL. ��. Initially you said OP gear was too low. Meaning he should of shifted up 1. Now you said his RPM too low, so he should of shifted down 1. Which one is it? OP states he was in 3rd doing 7-8k RPM. I’d assume he should of been in 2nd doing 8-9k RPM. Does higher RPM make the bike handle better or easier to get around corners or does RPM not matter at all?
for me (and my limited experience) i am riding s1000rr with 15/43 sprockets. i shift from 5th to 3rd for turn 1 and keep it in 3rd until exit of turn 6

run the highest rpm you can smoothly manage to maximize power to the ground. i could downshift coming into turn 9, but leaving it in 4th lets me (and my limited experience) go wfo sooner and thus put more power to the ground, ultimately going faster

Last edited by Smash Allen; 04-06-2018 at 09:40 AM..
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Old 04-06-2018, 09:40 AM   #22
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You’re confusing me here. LOL. ��. Initially you said OP gear was too low. Meaning he should of shifted up 1. Now you said his RPM too low, so he should of shifted down 1. Which one is it? OP states he was in 3rd doing 7-8k RPM. I’d assume he should of been in 2nd doing 8-9k RPM. Does higher RPM make the bike handle better or easier to get around corners or does RPM not matter at all?
There is no set RPM that dictates the gear. An SV650 at 8-9k rpm is almost at redline. An R6 is barely in the power band. Don't over think this. Don't even look at your tach or speedometer for clues on what gear to be in. Look at the drive you get out of the corner. If it's slow, powerless, with no grunt, you need to get your rpms up, the gear down. If you get a great drive out of the corner, you're in the right gear. Forget rpms. I couldn't tell you what rpms I am in at any corner at Thill.

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for me (and my limited experience) i am riding s1000rr with 15/43 sprockets. i shift from 5th to 3rd for turn 1 and keep it in 3rd until exit of turn 6
And that's the difference between a liter bike and a smaller bike. On my 1000 I will sometimes use one gear from T1 to T6, and often two. On my 750 I will always use two gears.
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Last edited by afm199; 04-06-2018 at 09:42 AM..
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Old 04-06-2018, 10:06 AM   #23
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run the highest rpm you can smoothly manage to maximize power to the ground. i could downshift coming into turn 9, but leaving it in 4th lets me (and my limited experience) go wfo sooner and thus put more power to the ground, ultimately going faster
thats not entirely how that works. "power to the ground" is actually drive force. drive force is higher in lower gears with the same power output. so, its very possible that ull accelerate quicker in 3rd at 70% throttle than 4th at 100% throttle. and of course, power output is determined by both throttle position and rpm. since the rpms are higher in lower gears, u get what seems like a lot more drive force at less throttle.

ultimately, the amount of drive force u can use is limited by the rear tire. so if you rode perfectly, say 10% wheel spin for maximum drive, the better drive is largely affected by when the tire stops spinning. if the spin stops when u are still in 3rd and/or u never spin in 4th, 3rd was likely faster. if you can spin the rear through 3rd AND 4th, using 3rd probably wasn't any faster. but of course, we don't ride perfectly.

IMO, most of the time ppl go faster in the higher gear for 2 reasons:
1. the throttle response is less nervous at a lower rpm and the max drive force is lower. so they feel more comfortable, allowing them to use more drive force.
2. their roll speed is higher because there's less engine braking and they had to manage fewer downshifts.
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Old 04-06-2018, 11:47 AM   #24
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thats not entirely how that works. "power to the ground" is actually drive force. drive force is higher in lower gears with the same power output. so, its very possible that ull accelerate quicker in 3rd at 70% throttle than 4th at 100% throttle. and of course, power output is determined by both throttle position and rpm. since the rpms are higher in lower gears, u get what seems like a lot more drive force at less throttle.

ultimately, the amount of drive force u can use is limited by the rear tire. so if you rode perfectly, say 10% wheel spin for maximum drive, the better drive is largely affected by when the tire stops spinning. if the spin stops when u are still in 3rd and/or u never spin in 4th, 3rd was likely faster. if you can spin the rear through 3rd AND 4th, using 3rd probably wasn't any faster. but of course, we don't ride perfectly.

IMO, most of the time ppl go faster in the higher gear for 2 reasons:
1. the throttle response is less nervous at a lower rpm and the max drive force is lower. so they feel more comfortable, allowing them to use more drive force.
2. their roll speed is higher because there's less engine braking and they had to manage fewer downshifts.
all that makes sense and agrees with my understanding. poor move to reference turn 9 i guess since wheelie tendency is the limiting factor rather than rear grip (at least in my limited experience)
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Old 04-07-2018, 07:10 AM   #25
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all that makes sense and agrees with my understanding. poor move to reference turn 9 i guess since wheelie tendency is the limiting factor rather than rear grip (at least in my limited experience)
Yes, T9 at thill is different than most turns because of the drop off exit, where wheelies come easily. I put an SV almost vertical there one day, being a bit over engaged.
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Old 04-09-2018, 03:48 PM   #26
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he was in race mode and his foot levered the rear off the ground

rain -> sport -> race -> slick (+/-7)
Gotcha. I keep forgetting that in those fixed modes, TC isn't adjustable on the fly. I leave mine in user-mode, program all settings same as Race mode & then adjust the TC setting as needed. (mine is the next gen)
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Old 05-01-2018, 09:04 AM   #27
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Which tires were you running? If you were on street tires that could explain a lot why the tires spun at that lean angle.
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Old 05-02-2018, 07:25 AM   #28
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Which tires were you running? If you were on street tires that could explain a lot why the tires spun at that lean angle.
I was on Pirelli SC1(F)/SC2(R). Rear pressure was ~28 in warmers. The rear tire was at the end of its life on the left side (wear bars almost flush with rest of tire's tread), so that definitely did not help. It was my 4th track day on these tires and I knew at the beginning of the day that I would probably have to change tires but the tires did not show any symptoms in the first sessions of the day.

If you look at the video (at the 20sec mark), it is debatable what happened first: scraping my boot/peg and lifting the rear and sliding, or sliding the rear and that's why you can hear the peg scraping sound (both happen almost instantaneously).
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Old 05-02-2018, 08:17 AM   #29
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however I added a tiny bit more lean as I came on the gas, .
That's is why you crashed.

It wasn't the tires, it was your technique.
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Old 05-02-2018, 11:33 AM   #30
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That's is why you crashed.

It wasn't the tires, it was your technique.
I was not arguing whether I made a mistake or not, by now it is pretty clear to me that my technique was wrong and I made a mistake.

The point about tires was just "had I had better tires would my mistake not resulted in a slide". I suspect it might have if I indeed slid before scraping, since that mistake in my technique could be more of a bad habbit (bad technique in general) rather than incidental, yet it did not cause me to crash before. Keeping in mind of course that the margin of error becomes smaller as speed and lean angles increase (as mentioned by others in this thread).

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