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I'm going to put this in general, not sure if it's the right place. Looking for a technical explanation on this one.

Why are the smaller bikes able to carry more corner speed compared to the bigger bikes? Does it really just come down to weight of the bike?

If it’s just weight, would a literbike that weighs the same as a 600 (assuming all other things being equal) be able to carry the same corner speed?
 

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The amount of force on the tires is absolutely derived partially from the mass of the bike.

The force applied to the tires is essentially equal to mv^2/r where m is the mass of the bike, v is the angular velocity of the bike and r is the radius of the corner.

Obviously this is simplified but that's the jist of it. Keep in mind that since we are working with the square of the velocity, deceases in mass are not directly proportional to increases in velocity.


Of course there are other factors to consider, but this is the foundation of it
 

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Discussion Starter #3
so to relate velocity in terms of mass using that equation (and I know it's generalization), v = sqrt ((Force on tire * radius of turn)/mass of bike)?
 

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yes.

so if you halved your weight, you would only get a root 2 (1.41) times difference in velocity, given the same available traction force and same radius.
 

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I had a similar conversation on another forum with some "self appointed" physics experts.

It went something like this...A heavier bike also has more downward force, which would give more grip. At some point the lateral force exceeds the grip, and that point doesn't vary much with the weight of the bike. A lighter bike should be able to get into corners quicker and accelerate out of corners quicker, but the actual corner speed doesn't change much.

I can't swear that this is true, but it seems to match my real world experience.
 

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There is also rotational forces of the larger crank and flywheel a larger CC bike has.
 

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I am no expert but my take is...on a motorcycle, lateral g (and also corner speed for a fixed radius turn at fixed speed) only depends on true lean angle given the tires can hold traction... so, if they both can reach the same TRUE lean angle, they should both be able to carry the same speed...(think about how hang-off affects center of gravity (and thus real lean) on a lighter bike and how weight/COG affects required traction to keep it from sliding)... In practice, I think for the the lighter bikes, its more to do with flick speed, braking and acceleration and less traction requirement which mean you can mix in more braking/accelerating in the lean...
 

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My CBR is about 175 lbs lighter than my VFR. I happen to have the some tires on each (Pirelli Angel GT). The CBR is way more flickable due to the lighter weight and less rotational mass. I can be more aggressive on corner entry on the CBR...later braking with a quicker turn in. However, once I am leaned over and committed to the corner I seem to be able to carry about he same speed on each.

Not exactly a scientific study, just my $.02
 

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Ever heard of the saying Power corrupts? Less power to deal with means more concentration for thinking about the corner giving confidence. A litre bike will go around the corner the same speed as a 600 but the 600 gives more confidence so that more people can achieve a higher cornering speed. Also I find litre bikes pull you into a corner which I think is flywheel mass? Someone else may know exactly what it is.
I couldn't believe how fast I could go around corners on a kawasaki er6. I literally didn't have to brake at all.
 

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I don't think individual experience can really be taken too seriously in this debate. Unless the individual is a pro level racer. Just because you can take a corner on your 1000 at the same speed as you do your 600 doesn't mean for a second that you are taking that corner at the absolute maximum of the bikes capability. You are likely taking it as the max speed you are comfortable with, which is irrelevant here
 

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Great video to break it down. Though the corner speeds mgp bikes carry vs moto2 are likely representative of their point and shoot approach vs flowing approach. This is touched upon in the video
 
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