ktk_ace
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Posts posted by ktk_ace
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I do not subscribe to MOTORRAD anymore, but I remember they stopped the K1300R in 36 metres from 100 kph (one G is about 39 metres) with ABS. At that point, it was the only bike where their test rider couldn't match the ABS, even after several attempts. At the same test, the Honda Fireblade stopped in 42 metres, quite typical for sportbikes. So why did the K, which is a lot heavier, stop so much better? Because it is long and low, meaning it can use both wheels for slowing and it will not endo. Short bikes with a high CoG is, as Code mentioned, limited because they want to roll over their front wheel well before all grip is used up. It's the price you pay for quick steering and loads of cornering clearance.
BTW, the first bike to beat the 40 metre limit in the German magazine's history was the RD350 L/C back in 1980, skinny tyres and all. It stopped in 39 metres.
the k1300R is by no means conventional... it has a very special front setup
Front duolever.
http://www.carbibles.com/suspension_bible_bikes.html
http://www.motorcyclenews.com/upload/219848/images/01bmw-k1300-r.jpg
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does electronics count?
eg:
-CBS (combined braking system)
-TC (traction control)
-EBM (engine braking management)
No, electronics will not change the maximum available stopping distances compatred to a skilled rider without these aids. Look at it like this: the earth is pulling you down with 1g, if you try to generate more than 1g in force laterally, you will start to endo or lock up. Unless of course there is additional downforce, lots of wind resistance from high speeds, etc.
Thanks for clearing it up
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He's using his huge leftover in his $10 of attention budget to doing all the work of modulating the throttle and clutch and constantly sampling the result.
I'm curious just how much easier the newer electronic packages have made this
Tyler
That's actually an interesting point. The MV Agusta F3 has the ability for the rider to adjust the amount of engine braking and a few other throttle related parameters which might help with that a bit. There's probably more bikes that have that option but I can't think of any off hand. As for the TC on most bikes all it does these days is retard the spark. TC would make that situation worse rather than better. You would have the TC adding to the delay of getting the engine RPM's up if it detected any kind of sliding or if the lean angle sensor got in its "oh no!" range.
If I understand correctly he's applying throttle and slipping the clutch to keep the engine speed synced up to the wheel speed almost like a long lasting rev matched downshift. If you REALLY wanted some cool electronics stick that into an electronic system! With the clutch for some riders being a redundant control an electronically assisted one would be interesting if they could get it right. Some of the new Italian bikes have an Auto blipper for downshifts and a quick shifter for upshifts. With an electronic assisted clutch synced into the bikes TC system it would be like having a sequential manual gearbox and much better TC and quicker on the gas time exiting corners. That would certainly translate into more attention spent elsewhere and perhaps better lap times.
Thats stock TC/electronics for you, its geared for insurance claims and safety
Get up to par on a race grade customizable TC/electronics unit and you will be plowing thru corners and conserving at least 15% of your tires , safety be damned LOL (its race grade,its meant to be all out ,nannying your mistakes is just a bonus but dont really count on it )
As for inline 4's... MOST 600/1000CC fully-faired supersportbikes are low on the TORQUE sweetspot hence the drive/rev matching needed. (exceptions will be the S1000r but its much more streetbike than sportbike)
the 4 wheel racing industry have this thing (i dunno what its actually called, any 4 wheel enthutiasts can chime in ??) that uses GPS to map a certain circuit and change engine/electronic characteristics for the car on certain parts of the circuit
-eg straight = all out power / mode A for maximum acceleration/top speed
-eg multiple low speed turns = reduced engine power / mode B for maximum control + tire conservation
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Interesting... so how much rider input is actually needed once the turn-in is complete?
hmm... none on the handlebars? (throttle is another thing, smooth roll on baby)
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Not to change the topic, but another thing I noticed is that the fastest lap (by far) in that video is the one where I brake the latest and hardest at the end of the straight (braking starts about 10:00) - you can see the front tire getting pretty squirmy, and I actually bump the zip tie on the fork a smidge. I know CSS is not big on super hard late braking, but in my case when I get that right it seems to make a difference. Probably that's just a measure of how poor my braking points normally are. Especially at the end of a long straight I have a tendency to coast or at least not brake very hard at some point during the setup for the corner. I think I need to work a lot harder at identifying braking markers, and moving them forward when possible. If there is time to coast, then there was room to brake later!
Of course what you are saying is correct. The only thing I need to correct is where you say "CSS is not big on super hard late braking". Braking is braking and you can and should brake as hard as you want as long as you don't find yourself rushing to a corner in a fashion that makes your entry rough or on the edge of crashing. Motorcycles only have so much braking capability and they have not changed much for decades on the straight line 60mph to 0mph stops. Compare the 60-0 stopping distance of a 1983 Honda Interceptor and a 2014 Yamaha R1. They are the same or within a few feet. You can only get about 1.0g's maximum of braking unless you have added downforce (like a wing on a car), uphill, added wind resistance (parachute or very large surface area), or at very high speeds where the wind resistance is extreme.
does electronics count?
eg:
-CBS (combined braking system)
-TC (traction control)
-EBM (engine braking management)
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Hi chris, a noob on the forum doesnt mean you are a noob in real life and vice versa
Great to have experienced members around to guide the younglings!! -
Skimming through this thread. How about some quotes regarding trail braking from Keith Code.
Probably the most fascinating thing about the subject of trail braking is that it is a very old subject that has been written about by Keith 32 (thirty-two) years ago. In fact he was the first to ever describe the technique for motorcycles in A Twist of The Wrist Volume 1, though he described the technique without calling it trail braking.
Here are few quotes. I have more if anyone wants.
"You back out of the brakes just as the turn takes over the job of compressing the suspension."
“Your target, or sub-product for any turn in which you brake and turn in succession, is timing the braking, steering and throttle so that fork and shock extension are kept as even as possible.”
I also have quotes about quick turning that will settle some confusions, but in actuality these type of confusions seem to stem from someone hearing another person "pick apart" some riding tech that they themselves don't understand. I may be smelling a little bit of this.
And to give a hint to anyone who needs it, if you are going to talk about steering rate, please consider all the attendant factors such as: speed, radius, lean angle, throttle timing and amount, camber, and desired outcome for a particular corner (e.g. hard drive out, set up for another corner that is faster/slower/same speed, etc.).
Thanks Dylan, that cleared up quite a bit of confusion for me : )
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front fork looks stock but has damper and oil changes
back is aftermarket preload adjustable.
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look at the motogp/WSBK and you will find the answer.
imho nope if at same skill level.
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imho it could be a bike centric problem.
the CB400SF for example loves to skid to the right (tailpipe side) if you3 e-brake the rear
the extra weight and position of the pipe is detrimental to one side's flickability so to speak as it makes handling not neutral.
I balance my own bike by adding weight until skids dont pan out in either direction
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imho bad if not horrid idea to ride spiritedly 2up.
ride slowly and within the legal limit.
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imho...
a noticably slower exit speed out of the turn and lower confidence + bike doesnt feel as planted due to decreased G forces from unoptimal lean angles. -
what KEEPS you from trying out riding on the track?
1) too far from where i live
2) Monetary issues
3) Racing culture here (lack of sponsors , hooligans on the tracks , horrid safety precautions and no run off areas )
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Hi there, welcome! Im the opposite of you, havnt attended school but have been here chatting up with the peeps here
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6- or 9-axis accelerometers are getting quite cheap, and are easy to combine with a GPS. But downloading, analyzing, and communicating the data to the student could be a big task. I guess this would be similar to the camera-bike setup.
Im with Khp
data acquisition is cheap and easy
but
turning it into useful information isnt
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Im cool with anywhere between 3-10 pounds of fat loss ... not muscle loss thou
Better diet
Better relationship with my immediate kin
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MD250 is listed unfueled at 194.XX lbs which is below 200lbs= wow!Hotfoot,
How much does that super single of yours weigh compared to the MD250 ??
Tyler
PS. which super single is that??
As Tyler already partially answered - the SuperSingle is a YZ450F dirtbike converted to a road racer. It has YZ450F motor, frame, transmission, etc., but the suspension has been shortened, it has roadracing wheels and fairing. I have done a lot to make it track ready (rearsets, GP shift, spools and frame sliders, fancy laptimer) but no engine work yet. I changed the gearing with the hope of getting a higher top speed out of it but haven't been able to test it out yet; if I can get it to top out at 125mph or so I'll be pretty happy and probably will leave the engine stock. It's still a kickstart, which turns some heads at the racetrack.
It is FUN to ride, very lightweight and flickable, plenty of torque; it has been a really interesting project, I've learned a lot in the process of getting it ready to race.
It is debatable whether it will be faster than the Moriwaki, it has more HP but doesn't handle as well, but it is a lot more comfortable to ride because it is much larger, and the torque makes it a kick to ride.
I wasnt expecting a formula 450 bike here , im very surprised in a good way!
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Hotfoot,
How much does that super single of yours weigh compared to the MD250 ??
Tyler
MD250 is listed unfueled at 194.XX lbs which is below 200lbs= wow!
PS. which super single is that??
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imho...
GET A BIGGER BIKE.
Bringing a 400 ti a litre class track / track day is the equivalent of bringing a knife to a gun fight ... you will be VERY outgunned.
This guy is riding an FZR400. He seems to be doing ok for himself with the bigger bikes. Hopefully some day soon I'll be making a video like that of my own.
If the track favors smaller bikes (lots of slow/medium speed corners) , sure.
if vice versa, you are really out of luck.
Which track? I would like to see the layout and give you a free assessment
You do have a very valid point there. On a track with a particularly big bias towards straight sections the more powerful bike will likely be at an advantage. The closest track like that to me would be Road Atlanta. The back straight would be very difficult to make up for in the corners if you were comparing lap times between the bikes.
Interestingly enough your original suggestion had been made to me by a few other people and I eventually ended up taking the advice. I bought an ex race R6. I'm just too stubborn to give up on a challenge. I will continue to ride the FZR400 occasionally until I learn it's quirks.
My goal is really just to improve my skill set. Learning how to maximize the strengths of a "slow" bike is probably not the easiest way to go fast I certainly admit. It's about having fun for me. Hopefully some day I can terrorize some R1's and R6's with my 24 year old clunker.
Well if you are light like hotfoot, a MD250 might fit the bill... But upkeeping it WILL be more expensive than off the shelf newer 600's.
or you can learn some new tricks , a kasaki ZX-6R 636 with traction control will be alot of fun to learn imho, esp when you step up to R-abc and tunable TC.
Whats your version of fun? would live to hear!
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imho...
GET A BIGGER BIKE.
Bringing a 400 ti a litre class track / track day is the equivalent of bringing a knife to a gun fight ... you will be VERY outgunned.
This guy is riding an FZR400. He seems to be doing ok for himself with the bigger bikes. Hopefully some day soon I'll be making a video like that of my own.
If the track favors smaller bikes (lots of slow/medium speed corners) , sure.
if vice versa, you are really out of luck.
Which track? I would like to see the layout and give you a free assessment
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imho...
GET A BIGGER BIKE.
Bringing a 400 ti a litre class track / track day is the equivalent of bringing a knife to a gun fight ... you will be VERY outgunned.
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sounds erriely similar to steering corrections .If the throttle is cracked and rolled a little, the bike does run wide. Then the rider might have to wait a bit for the bike to come back to the line he wants. There are some situations where it isn't necessary to roll all the way off (esses with the 2nd turn faster than the first, but even in those cases for sure stop rolling on).
But in a "normal entry" turn, with say braking before it, if the throttle comes on too soon, bike runs wider than it should and one has to then "fix" that.
Yep
And you might also miss your turining point... which is very nasty, one whole avalanche of things going wrong is gonna happen...
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Right on guys, exactly. Just to go all the way with this: if the front corrects, and the rider does ANYTHING to the bars, its going to be the wrong thing. Super light touch (after the steering is done). Easy to say, but...
CF
Possibly one of the hardest SR's to correct.
I say even harder than letting go after breaking up
Mladin On Going Fast
in Cornering and Techniques
Posted
the BMW S1000RR HP4 adjusts the damping rate every 10 ms for you lol