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Old 10-26-2012, 12:42 AM   #676
Harvey Krumpet
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My mentor swung past today. Prick of a man but I hold him in the highest esteem. I say this because in the course of our conversation he said that next time we do some training together I will have a rucksack high on my back with 10kg of sand in it.

Why? To make me ride smoothly, clutch, throttle, brake.Like liquid. I get his point........ Balance the mass, control & power.

Gawd, It's hard enough as it is!!

Any hoo. I see a funny video in my future..
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Old 10-26-2012, 04:17 AM   #677
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Originally Posted by Dzen View Post




Yes, it's a girl ;)
wow! and those other riders in the wet too!

rarely will I try to push any lean in the rain. I'd be redundant if I said anything about their skills, other than it showwwws!
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Old 10-26-2012, 04:35 AM   #678
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I'm not saying it's bad or slow. It is about cutting some time. I know how GS can turn, thats why I said that :)
By the way, I have another problem. Not enough lean! Probably it is fear of dropping my nice shiny bike... Full lock comes so quick, but turn radius is still wide on my VFR. Anyway, no chicken strips even on the front :)

on a figure 8, when is your heavy braking(not just trailing!) and when is your heavy acceleration?

do you feel the suspension compressing, or staying compressed during the tight turns?

full lock isn't something I concentrate on for tight turns , its no needed and may be -too much- input for the speed. usually l slide the front tire or drop the bike if I try to full lock on an 8 with speed. slower work turns with some clutch (walking pace) means lock comes easily. usually full lock is reserved for really tight stuff or slamming through a slalom.


if you don't have chicken strips, yiu obviously have skill, maybe you're carrying too much speed?

what's the end goal, full lock or faster times right now?

:)
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Old 10-26-2012, 05:41 AM   #679
Dzen
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on a figure 8, when is your heavy braking(not just trailing!) and when is your heavy acceleration?
braking starts 5-6m before turn and lasts till apex, front end compressed all the way to the apex and past till roll-on throttle

do you feel the suspension compressing, or staying compressed during the tight turns?
suspension is compressed and it helps turn harder

full lock isn't something I concentrate on for tight turns , its no needed and may be -too much- input for the speed. usually l slide the front tire or drop the bike if I try to full lock on an 8 with speed. slower work turns with some clutch (walking pace) means lock comes easily. usually full lock is reserved for really tight stuff or slamming through a slalom.
If you don't have chicken strips, yiu obviously have skill, maybe you're carrying too much speed?
I thought about that same way.
Main problem with the bike is that it has nearly 5m (may be little less) turn diameter even with lean and full-lock. So at walk speeds 8-s looks like not two falling drop shape but like two connected circles (literally).
In addition, huge radius cause less time to accelerate
Assuming that I have some solutions:
-full lock
-much lean
-much trail-braking to help turn tighter


What's the end goal, full lock or faster times right now?
Full lock is not a problem (honestly still not at 100% of turns used)
Goal is faster time. Now it 37.8
I feel like I can do 35.0 but it is still not so fast
:)
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Old 10-26-2012, 05:56 AM   #680
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cool. watching some of myself the tightest turns (smaller radius) happen with having all the braking and/or acceleration completed before the bike is completely over. it -seems- like the time is shortest when the turning speed is consistant, and weird enough, slower. turning faster = a bigger radius every time. (for me)

it seems easier (to me) to go slower around the actual turn, by doing all the acce / decel seperately and have turning speed set once the turn starts. nothing wrong with sliding in or spinning out of the turn, it feels NEAT, but i think it keeps the process from being smooth, and adds time to the run.

are you compressing the front end with front brake before the turn ?

using clutch through the turn, or any during the 8 ?

i get faster without the clutch, but the final gearing has to allow for both crawling speed and rev limiter in first (fairly low) for it to work well. keep in mind i'm on a drz with crappy dualsport tires. we're riding different animals !
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Old 10-26-2012, 07:21 AM   #681
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Quote:
Originally Posted by Dzen View Post

What's the end goal, full lock or faster times right now?
Full lock is not a problem (honestly still not at 100% of turns used)
Goal is faster time. Now it 37.8
I feel like I can do 35.0 but it is still not so fast
:)
From my personal experience from riding a Speed Triple which has a pretty big turn radius even at full lock and then riding for a limited time on the DRZ, where the front wheel can almost do a full 180 from lock to lock, I say full lock definitely helps.

My Triumph times were hovering in 36-37 seconds range, with me scraping my boots in the turns. With DRZ, it dropped to 34 with plenty of room to spare, and I wasn't even getting to full lock on it.

My theory is such. You need to worry about turning your bike as fast as possible through a turn around a cone, not the speed at which you do it. (Motogymkhanaman has actually mentioned this a number of times)

Basically you can blast right into it, and make a big circle going pretty fast with full lean, scraping pegs, but your time will suffer, because it still would be faster to slow down, get to the full lock, and just point the bike the opposite direction as fast as you can, which does not necessarily mean doing that at fast speeds.

So at the end, I would say its getting the most out of your skills (such as ability to ride at full lock), which should ultimately give you better times.



As far as the front brake. Again from personal experience, I started putzing with it again, doing that 24 foot circle exercise. So instead of slipping the clutch, I'm dragging front brake as well, increasing pressure a bit, when i see I'm going wide and about to leave the circle.
I've also started doing a 80 foot figure 8, just for practicing the front brake into the turn. 80 feet (instead of GP8's 40 feet) gives me enough space to accelerate and mentally prepare to the turn, so its a more of a relaxed pace for my head. What I'm noticing, at hard braking into the turn, is when you are already leaned in, the front end wants to turn into the turn by itself.

So here is another theory.
If you are going in too fast, and you squeeze your front brake hard, inside the turn, the front end will try to twist into the turn. If you resist it, the front tire will start to skid as there is too much speed and too much momentum of the bike for the rubber to grip, and you are resisting its natural motions.
If you do let it turn into the turn, but again there is too much speed, the tire can still skid, and the bike can flop over if you are not ready for it.
However if you get it right, and you brake hard while you are still upright, and then keep braking into the turn, but already after you scrubbed off enough speed before leaning, you front end will twist into the turn, don't resist it, and counter balance the bike a bit, so it doesn't just plop to its side. This should give a fast and tight turn around the cone.

Am I even remotely on track with my theories?

I'm getting a little bit more comfortable with the front brake, so I will soon go back to the 40 foot GP8 and time myself to see if I'm improving.
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Old 10-26-2012, 08:02 AM   #682
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vulfy, sorry, I may have not been clear...

full lock will definitely need a slower turning speed, and more control. its -good- and like you said likely required to be fast on a sport bike. you guys on sportbikes really are something to watch. on the SM's it doesn't feel needed as they turn so much sharper without hitting the stops.

....trying not to muddy the water any more than I have.....


:)
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Old 10-26-2012, 08:29 AM   #683
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Dunno... maybe.... I wasn't able to get to full lock on my DRZ so can't say from experience.
However after watching Dredman's video

http://www.youtube.com/watch?feature...&v=jbx7SvIloiE


You can see the guy twisting his bars fully to full lock and you can see how tight his turn circle is, and how fast he rotates full 360. Turn lock on that bike looks close to what DRZ has.

Of course at a bit more speed it will be more difficult and as you said, might not even be needed at all, but I think that dirt bikes and sumos have a pretty big advantage over some of the sport bikes, with that larger lock to lock twist. So if we can use it fully, should only be to our advantage.
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Old 10-26-2012, 10:33 AM   #684
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As I understand from bike physics theory, each turning radius have only one possible speed and lean angle (with everything else equal). So, assuming full-lock radius we have many possibilities from almost vertical bike and slow speed on one side and run-like-hell speed with insane lean angle on the other side, but turning radius is equal in any cases (actually it's a bit tighter in second case). I fully agree with rule of "faster turn - faster time" but in case of full lock only solution left is speed and lean. Again, I've tried many other bikes with much tight turn capabilities and have no problems with radius at all, only my fear of falling and scratching other's bike :)

I'm leaning into turn on fast and wide turns and counterbalance outside in tight and slow ones. It comes almost instinctively.
I don't use clutch, even in slow turns, just add some power with hold-it-on with rear brake. Bike itself has tendency to jumping and jerking on idle.
Trail braking helps me to swirl into the turn MUCH and there is nothing like widing the turn. By the way I have my own trajectory on 8-th I try to start turn far from cone and out of turn near it, so "8" is like shifted aside of vertical line formed by two cones.

I think it is not correct to compare my time on my VFR to time of PROs on, say, NSR250 :)
Anyway for me it's just fun and my goal is to improve my technique on the bike I have.
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Old 10-26-2012, 11:17 AM   #685
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Vulfy has it just about spot-on. Remember that it is the rear wheel we are steering around the pylon and the front is only there to keep the bike from falling over. Remember also that at full lock and full lean the sterring geometry is wildly different to what we experience with the bike upright, so the feedback we get from the front will be wildly different as well.

The rate at which the bike capsizes (leans) and the steering angle increases gives us the size of spiral track on the ground. Faster capsize/steering angle increase = smaller spiral. Our aim is the smallest possible spiral leading into the smallest possible radius to carry us around the pylon.

A lot of novice Moto Gymkhana riders only manage to achieve their max lean angle just as they are about to exit the pylon which means that their spiral is way too long and their radius is way too short. Taking a look at a good rider, you can see that the entire turn is about 50:50, half spiral and half radius. Real experts like Noboru Yoshino have a ratio of around 30:70, i.e. 30% spiral and 70% radius, but by his own admission, that took him about five years of constant practice to achieve!
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Old 10-26-2012, 11:21 AM   #686
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Anyway for me it's just fun and my goal is to improve my technique on the bike I have.
Well said! I have no illusions about being a competitive gymkhana rider -- at least not yet However, I find that gymkhana practice is very enjoyable, and makes me a better rider on the street, so whether or not I can ever go head-to-head with the best of the best, I will at least become a better rider than I am now.
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Old 10-26-2012, 12:08 PM   #687
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Well said! I have no illusions about being a competitive gymkhana rider -- at least not yet However, I find that gymkhana practice is very enjoyable, and makes me a better rider on the street, so whether or not I can ever go head-to-head with the best of the best, I will at least become a better rider than I am now.


Its all good. Obviously even the pros do it for fun, as Gymkhana is not really a money sport and you can't make a career out of it (not yet at least).

So we all understand, that everybody here is doing it to the level that they enjoy.

But man those Japanese riders make it look easy!!! I've been sitting at work, on my lunch break, browsing some of their videos on Youtube, and a coworker passes buy, and asks...

"What is that?"
"Oh this is Moto Gymkhana, basically an obstacle course on a motorcycle."
"Oh... Well that doesn't look too hard, all they do, is go round in circles!"

Of course he is a smart-ass and said that with a big grin, but man oh man those circles get tougher and tougher the more you learn how to ride them.
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Old 10-26-2012, 02:04 PM   #688
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Originally Posted by Vulfy View Post


Its all good. Obviously even the pros do it for fun, as Gymkhana is not really a money sport and you can't make a career out of it (not yet at least).

So we all understand, that everybody here is doing it to the level that they enjoy.

But man those Japanese riders make it look easy!!! I've been sitting at work, on my lunch break, browsing some of their videos on Youtube, and a coworker passes buy, and asks...

"What is that?"
"Oh this is Moto Gymkhana, basically an obstacle course on a motorcycle."
"Oh... Well that doesn't look too hard, all they do, is go round in circles!"

Of course he is a smart-ass and said that with a big grin, but man oh man those circles get tougher and tougher the more you learn how to ride them.
Yup. Exacary what I am finding. As I learn better technique & push a little more it gets scarier & scarier. Sometimes I feel as if I'm not really progressing but then I look at some vids from months ago or do something when I'm out for a run..... like pulling away with the bike on a tight lock or doing a u-turn in a tight space. I couldn't comfortably do that awhile ago.
Using the front brake into the turn is my handbrake at the moment too, I'm doing it but the rate at which the bike turns is a bit scary, it really does come around fast & I'm neither smooth enough nor co-ordinated enough to let it follow it's natural course like motogman says. As the lock swings around & the bike drops I go rigid & swear a little.
This was the discussion I had yesterday, my mate said when I think I've got it sussed he's going to make me do it with a lot of weight up high to make smoother still. Be awhile yet......
This guy can do the GP 8 on his Deauville with my G/F as pillion faster than me on the DT.... Bassid!
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Old 10-26-2012, 06:00 PM   #689
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Originally Posted by Motogymkhanaman View Post
Vulfy has it just about spot-on. Remember that it is the rear wheel we are steering around the pylon and the front is only there to keep the bike from falling over. Remember also that at full lock and full lean the sterring geometry is wildly different to what we experience with the bike upright, so the feedback we get from the front will be wildly different as well.

The rate at which the bike capsizes (leans) and the steering angle increases gives us the size of spiral track on the ground. Faster capsize/steering angle increase = smaller spiral. Our aim is the smallest possible spiral leading into the smallest possible radius to carry us around the pylon.

A lot of novice Moto Gymkhana riders only manage to achieve their max lean angle just as they are about to exit the pylon which means that their spiral is way too long and their radius is way too short. Taking a look at a good rider, you can see that the entire turn is about 50:50, half spiral and half radius. Real experts like Noboru Yoshino have a ratio of around 30:70, i.e. 30% spiral and 70% radius, but by his own admission, that took him about five years of constant practice to achieve!
I'm not certain what you ate taking about,please explain ,or draw a diagram ?
If you draw it,I'll give it a go and video it!
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Old 10-26-2012, 06:16 PM   #690
Harvey Krumpet
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I'm not certain what you ate taking about,please explain ,or draw a diagram ?
If you draw it,I'll give it a go and video it!
Have a wee look at THIS Posted earlier in the thread. Watch where the riders start to turn, well before the cone & how they use the front brake to help start the turn, with the front brake applied the bike "falls" in quickly. Notice how tight the rear wheel turns around the cone compared to the front.
I can't explain it but if you watch the vids a few hundred times the technique slowly becomes apparent, as opposed to actually doing it which is in the realms of magic!
I'm sure MGman will expand on this soon.
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