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Yes. That does answer the question.

However when trailing the brakes does it require less handlebar pressure? Most riders report that under trail braking the steering feels heavier meaning more resistance at the handlebars. Along those same lines most riders report that under throttle the handlebars feel lighter.
I get similar feedback from riders new to trail braking. The handlebar will feel heavier with more braking before the bike is leaned over. After the bike is leaned over (~30% lean) the brake will cause the bike to lean easier due to braking and centrifugal forces changes. Also, if you look at the tire profile, it's flatter above the shoulder area, more curvy closer to tire edge which causes the bike to lean faster after past a certain lean angle.

Finally, one of the most common reasons why a bike is harder to turn is not having proper front tire PSI. I.e, on my front I run SC1 38 PSI or SC2 36. 1-2 PSI lower in the front will make a difference.
 

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Loading the front brings weight forward to reduce the fork length and thus steepens the head angle. Which has and affect of reducing the specific force to turn the bars and does reduce the force needed to hold the line. People put the forks through the triple clamps to achieve the same without trail braking. Trail braking is the correct method, dropping the triple clamp is a crutch.

Rotating mass reduction is much more relevant to change of direction forces.

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Actually I will simplify.

Reduced wheelbase from compressing the forks, reduces the turning circle of the bike so that for a given effort you turn more.

Its not less effort, its increased output in the form of turning.

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Discussion Starter #44
So if we had one rider approach the same corner in two different ways, which one would take less effort to steer the bike:

A) Trailing from 80mph to 60mph.
or
B) Entering at 60mph without trailing.
 

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A) Trailing from 80mph to 60mph. Requires less steering effort and faster.
 

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So if we had one rider approach the same corner in two different ways, which one would take less effort to steer the bike:

A) Trailing from 80mph to 60mph.
or
B) Entering at 60mph without trailing.
Effort is a factor of speed. 60 mph entry will not require as much TOTAL effort (gforces acting upon him etc) to turn but rider 1 gapped him and maintained a higher avg speed whilst being able to turn tighter for a given steering effort. Because he used changes in the geometry to his advantage. With no added risk.






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Yes. That does answer the question.

However when trailing the brakes does it require less handlebar pressure? Most riders report that under trail braking the steering feels heavier meaning more resistance at the handlebars. Along those same lines most riders report that under throttle the handlebars feel lighter.
Loading the front brings weight forward to reduce the fork length and thus steepens the head angle. Which has and affect of reducing the specific force to turn the bars and does reduce the force needed to hold the line. People put the forks through the triple clamps to achieve the same without trail braking. Trail braking is the correct method, dropping the triple clamp is a crutch.

Rotating mass reduction is much more relevant to change of direction forces.

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A) Trailing from 80mph to 60mph. Requires less steering effort and faster.
i'm seeing two contradicting items above. Dylan said "Most riders report that under trail braking the steering feels heavier meaning more resistance at the handlebars. Along those same lines most riders report that under throttle the handlebars feel lighter" but Alex and zoo are saying less steering effort under trail braking. I can see the logic behind both though.

i would agree that trail braking lowers the front, decreases the rake, making it more flickable for lack of a better word. it also improves traction of the front tire reducing chance of low siding.

i would also agree that a loaded front end increases the friction between the tire and the surface, possibly requiring more force to turn the front wheel off it's current path.

so which is it? or maybe it depends on the geometry to even answer this? my guess is under trail braking since that's a proven technique?
 

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Depends on the corner phase they are talking about. Amateurs are rubbish at differentiation.

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@Dylan Code , since CASS has some cool gadgets to helps us learn, perhaps an xsensor pressure measuring map wrapped around some handlebars would be a cool experiment? could take data coming into the curve, following a set line, first trail braking, then figure out at what speed you turned, then set cruise control at that speed and do a constant speed through the same and compare? happy to help map it out if you want to explore it.
 

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Inertia from spinning engine is also a factor, which means that different engine configurations also has an effect on steering effort.
Inertia from engine and transmission are almost insignificant.
Typically the difference between a 600 cc and 1000 cc comes from geometry; trail.
Typically a 600 has shorter trail than a 1000cc.
And trail alone is the most significant factor for steering effort.
 

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I get similar feedback from riders new to trail braking. The handlebar will feel heavier with more braking before the bike is leaned over. After the bike is leaned over (~30% lean) the brake will cause the bike to lean easier due to braking and centrifugal forces changes. Also, if you look at the tire profile, it's flatter above the shoulder area, more curvy closer to tire edge which causes the bike to lean faster after past a certain lean angle.
That is total bull ****.

If you lean a bike, any track bike, the more you lean, the more stable the bike (geometry) will be.
The more you lean, the more you need steering effort.
 

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Loading the front brings weight forward to reduce the fork length and thus steepens the head angle. Which has and affect of reducing the specific force to turn the bars and does reduce the force needed to hold the line. People put the forks through the triple clamps to achieve the same without trail braking. Trail braking is the correct method, dropping the triple clamp is a crutch.
One thing which is forgotten (in your comment) is speed.
The slower you ride, the less you need steering effort.
If you ride fast, you have a lot of kinetic energy which wants to go straight forward.
The more you trail brake, the slower you ride.
 

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So if we had one rider approach the same corner in two different ways, which one would take less effort to steer the bike:

A) Trailing from 80mph to 60mph.
or
B) Entering at 60mph without trailing.
B.
 

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Amateurs are rubbish at differentiation.
Pro riders have the very same problem. If you watch different youtube channels, you will see/hear all the legendary myths.
For example WSBK world champion/ campions will repeat some of the same myths that are heard in any track day paddocks.
 

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So if we had one rider approach the same corner in two different ways, which one would take less effort to steer the bike:

A) Trailing from 80mph to 60mph.
or
B) Entering at 60mph without trailing.
A) as trailing compresses front and reduces wheelbase
 

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@Dylan Code , since CASS has some cool gadgets to helps us learn, perhaps an xsensor pressure measuring map wrapped around some handlebars would be a cool experiment? could take data coming into the curve, following a set line, first trail braking, then figure out at what speed you turned, then set cruise control at that speed and do a constant speed through the same and compare? happy to help map it out if you want to explore it.
There are already a lot of data available in internet, just use google/ try different search words, you might need do pay a few dollars to get some of the documents.
But anyway the truth is already out there. :)

And if you want a theoretical approach, just read; Vittore Cossalter - Motorcycle Dynamics, and you will be able to answer to your own questions.
 

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There is a subtle part to Dylan's question. If the goal is purely less steering effort, then option B would win (no braking forces to resist steering), but it also the slower option around a corner. My answer is assuming that corner speed and faster laptimes are also the goals, not just steering effort. It's a no brainer that a bike without any braking will require less steering effort, but it also will have slower cornered speed and laptime.
 
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