gianco
-
Posts
22 -
Joined
-
Last visited
-
Days Won
2
Posts posted by gianco
-
-
mmmhhh understood
very helpful
thank to every one for time and explanation
now i try to verify tyre and setting!
-
1
-
-
ok i understood
but the thing that has surprised me,
is that i was thinking that, when one say:
with more trail, fork more upright,bike has more stability, was meaning that the bike want stay more upright and not cornering, but instead i see that it is easy to go down without press on imternal handlebar.
i try to explain better,
on same bike ,with lower front,it has less trail, fork more upright, it should be more flicker more unstable,
instead it try to stand up itself and in cornering it has to be pushed on internal handlebar
what intry to explain is that i understand why it physically do this,
but i don’t understand why it is sayd more unstable?
a bike that itself try to stand up, it shouldn’t be colled more stable?
-
hi!
sorry for my english i’m in italy.
i ride bikes by many years, sometimes track.
i’m able to knee down, but i’m not a fast rider.
i’have searched extensively on web, read many books,
but still haven’t a answer to my question.
when i’m cornering with my bike,
i countersteer, and bike lean,ok.
but when leaned, i feel that handlebar, try to push against hand,(turn side, internal side)
i’m trying to understand the influence of suspension setup on this behaviour.
i think i understood, that if the front end is lowered (reducind preload on fork spring or lowering fork tube in triole clamp)this behaviour is pronounced
instead if rise front end i fell this nearly gone,
i’m wrong?
-
analyzing myself
i can say, i found that, the issue is the scare of lean....
with body i force to hang off and lean bike, and with arms i fight against it,
trying to steer inside turn, so uprighting the bike.
now that i'm riding with pitbike on track, this is becoming more conscious....
the bike has nothing wrong, it's my limit....
-
no
for now i bought a pitbike and i'm training in track
later i'll go back on track with my bike
-
i feel like preventing bike lean
i'm holding with lower body
-
bicycle no
sorry never drived bike like dirtbike or pitbike
-
2 minutes ago, Jaybird180 said:
Have you considered giving that a try?
yes i'll try,
but my need is to undestand in what i'm wrong
-
14 hours ago, Lnewqban said:
Gianco, why do you think that pushing on external handlebar while cornering is wrong?
Some bikes are naturally under-steering, yours may have that tendency for the tires that it is wearing. That means that the front tire will try to under-steer by itself when leaned. By keeping pressure on the external handle, you are compensating for that tendency and keeping everything in balance. You know exactly how much pressure to keep by feeling the bike balanced while cornering (not falling into the turn or out of it).
Whenever you are "too slow for that moment" or at the ideal cornering speed, the bike is leaning exactly what it needs to lean to keep lateral balance of forces for that particular speed/radius-of-turn combination.
As soon as you released the external pressure that was necessary to compensate for the under-steering tendency of the bike, a small counter-steering happened by itself (the internal handle-grip moved forward some), which leaned the bike excessively for that speed and you immediately felt the bike was falling into the turn (the lateral balance of forces had been ruined).
Remember, we never directly select the lean angle, we only choose speed and radius of turn; then, the bike leans as far as it needs in order to find the lean angle that balances all lateral forces. By hanging-off we reduce the lean angle of the chassis, but the dynamic lean angle of balance (of the combined center of mass) remains the same for same speed and trajectory of the curve/radius of line.
mmmhh not sure is like that in my case,
because, i feel like i'm fighting,
on one side with extreme body lean and other side outside bar push,
i feel can take same corner same speed without knee down, with less fatigue, less lean, but not pushing in external bar,
i feel like fighting my body against external bar push
-
1
-
-
7 hours ago, Apollo said:
Fear of leaning too far can be one factor for keeping pressure on the handlebars. Part of it may simply be reminding yourself not to have pressure. Another bigger thing may be addressing why you feel fear. Maybe it is a visual issue with looking far enough down the track.
Also, are you supporting your body weight through holding the handlebars? This may also cause the tense arms if you are trying to hold yourself up by gripping the handlebar. Fixing this requires improving your lower body contact with the motorcycle. This might be addressed by looking at how you use your outside knee to contact the tank. If you were to give a percentage (%), how secure does your outside knee to tank contact feel when cornering?
P.S. It's a bit of a trek, but not too far to consider checking out the UK operations of the school to have a coach work in-person on these issues. Often, an external set of eyes can identify issues that you're unaware of.
i feel in strong contact with bike,
i could leave the handlebar.......
except in that moment when i feel push on external handlebar
and that happen on my max lean
i'm feeling like i 'm trying to lean off excessively with bike leaning way less.
-
for sure if i was near , i choose to go that school👍🏻👍🏻
but i'm in italy..
on day 30 of this month i'll try it:
http://scuoladimotociclismo.com/
what is that steering drill?
can be explained?
-
today at track, after many times of trackday,
i realized that meanwhile i drag knee down,
i'm pushing on external handlebar.
i know is really wrong.
as soon as i realized it, i tryed to release pressure, suddently bike, leaned more and turned more inside the cornering,
but i felt i was"too slow " for that "moment"
i think it's the fear of lean angle,
instinctively i try to keep bike upright.
how i can, force myself to not push outside bar?
( i have a bmw s1000xr)
i'm that in photo
-
understood...
for aching knee,
i think like you say....
i was wrong, to press foot on internal footpeg,
i was trying to turn bike excessively with body lean and poorly with countersteering.
now i began to apply more consciously countersteering,
i feel , less pain in knee.
i have to force myself to, remeber to coontersteer, end not rely only on body steering.
i realized that , if i force the bike only with body lean, o press very hard with my weight on footpeg.
now i'm learnig instead, to use external knee for anchor, and another thing i understood,
is that, isn't really helpful to try to put body weight on footpeg,
it drive rapidly to aching knees,
instead, if only use footpeg to shift body lean, and after put weight on seat, the internal knee is relaxed,
understood, that when bike alteady leaned,
there isn't need to press on footpeg
-
hi!
i have a question,
is my internal foot position right?
i have a bmw s1000xr
and touch knee down on track,
but i feel aching knee , i rapidly feel fatigued.
i see that people that ride supersport put internal foot near vertical ,
but i'm not able to do it...
i put the foot more or less pointing in front,like the foto of naked bike, (also if it isn't myself)
maybe that on a naked type bike the footrest are not toward rear , and force to that position?
-
1
-
-
the difference in ginkana technique is that the max lean is obtained at low speed ?
i'm right?
-
mmhhhh very interesting!!!
undestood some principles that were "growing " in my head , but that i was not able to reach
-
in other word the bike steer also because the bike wheel can be seen as a cone
and a rotation of a cone decribe a radius rotating
-
quote from tony foale book:
2-20 Tyres
Camber force (thrust)
The previous section explains how steering a wheel generates the force necessary to force a vehicle to turn around a bend. However, bicycles and motorcycles must lean when taking a corner and this leaning also creates a lateral cornering force. In fact at all but the slowest of speeds and cornering accelerations this force will likely be the major contributor to the total cornering force, and the steering effects will just make up for the difference between the required cornering force and that provided by the lean. Hence, the degree of steering necessary on a motorcycle is much less than that required by a car. The lateral tyre force due to the tyre camber angle is known as camber thrust or camber force. Let’s look at Fig. 2.18 to see how this force is created.
Fig. 2.18 The top left sketch shows how the contact patch of the tyre flattens at an angle and effectively becomes a slice of a cone which tends to turn around the geometric apex of the cone. The other two diagrams show how this cone tries to turn a tighter circle than the actual bend radius.
As the inside edge of the tyre is forced to adopt a smaller radius than the outer edge, then for a given wheel rotational speed, the inner edge would prefer to travel at a slower road speed, this happens if the wheel is allowed to turn about a vertical axis through the apex of the cone. Just as a solid cone on a table would, if given a push. If the bike was leaning over at 45° then for a normal size tyre the horizontal radius to the cone axis would be approximately 450 mm, an impossibly tight turn. However, we’ve seen before that Conservation of Momentum will want to make the bike go straight which tends to work against this desire to turn about the effective cone centre, these conflicting effects will form a balance where the actual corner radius described is considerably greater than the cone radius.
-
11 hours ago, Lnewqban said:
Your language is good enough for us to communicate about dynamic of motorcycles, my English is not much better.
According to Newton, everything that has some speed wants to move on a straight line by itself and must be forced to turn.
The forces of steering (wheels pointing in different directions) and friction between tires and pavement are the only things that force a car, truck or a motorcycle to turn, not the lean of the bike.
A motorcycle can be leaned and still move on a straight trajectory if both tires are kept perfectly aligned forward.
We only lean the bike to create a balance of forces between gravity and centrifugal effect and that balance is kept during the turn regardless of how much the rider hangs off.
The more you lean a bike, the less misalignment both tires must have to keep the same circular trajectory and the front contact patch moves away from the rear one, which means less steering is needed (although the difference may not be noticeable).
One of the reasons is that the distance at which the axis lines of both tires intersect each other must increase as the bike is leaned in order to keep the same horizontal radius of the curve.
Please, take a look at these schematics and text in Italian:
http://www.dynamotion.it/eng/dinamoto/8_on-line_papers/Pneumatici/Pneumatici_ita.htm
no no!
not so simple....
in that link is explained the correlation of sticking forces of tyre on tamrac, and tyre lean, and "deriva"
but don't concerns my question
and many assumption you made are wrong
read the book of tony foale on chassis deigns....
you'll be amazed of many info!!
if what you says was true, the rider that do japanese gimkana, due to high leaning of bike, shoud have handlebar no steered,
instead they combine both steer full stop lock and hig lean angle
-
you have done the perfect abstract of what i learned in last times.
but the perplessity is on what makes the bike turn the same but with less lean.
-
hi to everybody
sorry for my language,
i'm italian.
i have a question....
i have readden many books,done some track school and track days here in italy,
put easily knee down,
but there is a question that i'm not able to answer...
before some considerations...
if the turning of bike is determined by leaning and steering of handlebar ...
and....if body hanging determines less bike lean angle(at same speed and radius of turn)....
------answer-----
when we do a turn, hangin off , bike lean less, what make it turn the same as it was leaned more (without hangin off)?
what i mean is:
in same turn , same speed,
if we hang off, the bike make same turn, but less lean, what makes it possible?
more handlebar turn?
in a car what makes it tur is only steer,
in a bike it is turn and lean at various degree
i'm courious what makes it do same turn with less lean....
steering feel
in Cornering and Techniques
Posted
yes
and i discovered that if i rised the front,
this push on internal handlebar is less needed.
as you in tyre change.
and i was asking why....