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Discussion Starter #1
Fellas, Just as a survey question: When in a turn after you've set your body up for it, butt off seat, relaxed your body and arms, etc...

Do you keep your weight on the inside peg with your foot, or do you just weight the seat with you butt by sitting down?

And how does this effect the center of gravity while in the turn? With weight on pegs is should be lower than if you butt is resting on the seat correct?

Just curious, because i've been supporting my body weight on the pegs more lately while mid turn and it feels much more stable then if i'm just sitting on the bike mid turn. (I'm not hovering over the seat mid-turn, but I'm really weighting the pegs more so with my feet than my butt)


How about you guys?
 

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I never paid any attention to how much pressure to put on the pegs. It doesn't help with centre of gravity, because you don't shift weight by pushing on something. If you can't go any further because of scraping hardware or limited by tires, you can get your body low and on the inside of the corner. That's the only way to really change centre of gravity!

Some say you have to hug the tank with your knees, I never did that either.. for some reason! But if it feels ok for you, why stop doing it? Just don't get cought out paying more attention to the pushing then you should.. :)

Come to think of it, maybe you have a better feel what the bike is doing through the pegs then through the seat?
 

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I would say most of my weight is on the inside peg with the rest through the remaining butt cheek on the seat and the inside of my opposite thigh gripping the tank :O
 

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Interesting question.

If your bum is on the seat the weight will be on the seat and the centre of gravity centred from there.

it the weight is on the pegs then the cof g would be somewhat different.

if your wieght is on the seat then the weight distribution is to the rear as your bum is over the rear whell and the suspension will respong accordingly.

If your weight is on the pegs then the suspension will see your weight as central and respond accordingly.

This gets interesting if you encounter a bump mid corner coz the bike is now freer to move with you as a semi suspended component.

I'll have to experiment to see the effect myself but this is one example that does work .

drive into a shopping centre and ride over the speed bump sitting down. the bike will lurch for and aft and you will too.

now ride over it semi standing up and the bike is freear to move and your wieght will have less influence.

not sure how that translates to cornering. as I am a bit of a mike hailwood style rider. bum on seat .

consistent riding would suggest finding what suits you and working with it.

whatever your choice it will influence how you set up your suspension. If like me you sit tight on the seat and ride the back wheel more then my rear suspension is probably a little more agressive in the damping. and front set softer to smaller bumps and progressively harder for the harsh ones.

Dirt riders move their wight on their feet to influence the traction steering characteristics. not sure about bitumen but inside weight steer more in outside weight run wider.
 

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Discussion Starter #5
that is the first thing that I've notice is that I have a ton more feel through my feet than through my bum. And like i said before I'm not hovering over the seat by I'm feeling through my feet because I'm like weighting the inside peg and my outside thigh is hugging the tank. It's wierd!! I'm going canyon riding tomorrow after work with a buddy of mine so I'll give an update.
 

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the position of your center of gravity is not dependent on which part of the bike you are weighting :no center of gravity is only dependent on where your center of gravity is placed irrespective of how you are hanging on.

i think the best position/weighting point is the one which has you relaxed the most. your obviously going to need to shift your weight to the side the faster you go, just do it in the most relaxing way. you can really feel whats going on with the bike and tires when your relaxed.

a racers i talked to told me that the fast guys have most of their weight on the inside of their outside thigh. he said when you get really good you should be able to remove any foot or hand from the pegs or bars mid corner and not have your cornering affected. heaps of examples of this in MotoGP with riders taking their inside foot off the peg to help get the bike turned in or taking their hands off the bars to give other riders the bird. :laugh
 

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I find I weight the inside peg, but still leave a fair bit of weight on the seat because I'm a fat lazy unfit bastard :laugh

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The higher the CoG the better. The closer to the inside of the corner the better. If you crouch and lower the CoG it puts more lateral force on the tyres. Many think a lower CoG is better, but it's not. So you hang off to get the CoG closer to the inside. But you should sit high rather than crouch. A higher CoG will act as a larger lever trying to stand the bike up, but have less sideways push on the tyres. So rather than trying to kiss the mirrors, try and kiss the air above them

This scan is interesting especially the last two pictures. Take note of the Yellow circle indicating the CoG too.




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I'll have to experiment to see the effect myself but this is one example that does work .

drive into a shopping centre and ride over the speed bump sitting down. the bike will lurch for and aft and you will too.

now ride over it semi standing up and the bike is freear to move and your wieght will have less influence.
But I think most of that effect is because your legs become shock absorbers for your body rather than having the force of the bump shoved up the base of your spine and the suspension has to carry the bike weight and the rider's weight as one lump. So rather than being a CoG thing, it's more of a shock absorbing thing, your legs become and extra set of springs and dampers for the rider weight. :dunno But putting the CoG centre to let the bike see-saw might help a bit.
 

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My weight is usually distributed pretty evenly. Still pressure on the pegs, a lot of weight on the thigh that slid over and took the place of my butt, I'm usually tucked which puts some weight on the fore-arm resting on the tank. (ingenious design that tank)

So I'd say there's a lot of contact points, makes it easier to adjust to flick to the other side.

C
 

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I would say most of my weight is on the inside peg with the rest through the remaining butt cheek on the seat and the inside of my opposite thigh gripping the tank :O
Are you sure? I can't believe you race your bike and are constantly putting your weight on one leg, that could be quite tiring :O

Interesting question.

If your bum is on the seat the weight will be on the seat and the centre of gravity centred from there.

it the weight is on the pegs then the cof g would be somewhat different.
Centre of gravity does "not" change that way. Unsprung mass, oil, gas and coolant do.. so does the rider. Centre of gravity is defined using mass, not forces like pushing. You can look it up here: http://en.wikipedia.org/wiki/Center_of_mass

If centre of gravity changed by pushing on the pedal.. then the bike would change direction when you push a peg while being mid corner!

This gets interesting if you encounter a bump mid corner coz the bike is now freer to move with you as a semi suspended component.
That's something else.. with acting like suspension you disconnect your weight (partly) from the bike! Being part of the suspension can be really usefull, I think best examples are mountainbiking, trial biking etc. But I don't think it'll help much on a motorcycle in corners..!

I'll have to experiment to see the effect myself but this is one example that does work.

drive into a shopping centre and ride over the speed bump sitting down. the bike will lurch for and aft and you will too.

now ride over it semi standing up and the bike is freear to move and your wieght will have less influence.
Exactly! I think that's because the suspension isn't sufficient for such big things, and the short wheelbase doesn't help either! So then it does help to stand up, but very small bumps.. well we have suspension on the bike for that don't we?

not sure how that translates to cornering. as I am a bit of a mike hailwood style rider. bum on seat .

consistent riding would suggest finding what suits you and working with it.

whatever your choice it will influence how you set up your suspension. If like me you sit tight on the seat and ride the back wheel more then my rear suspension is probably a little more agressive in the damping. and front set softer to smaller bumps and progressively harder for the harsh ones.
:)

Dirt riders move their wight on their feet to influence the traction steering characteristics. not sure about bitumen but inside weight steer more in outside weight run wider.
Yes they do, they change centre of gravity by moving quite a bit on the very long buddyseat! With that they influence how much "weight" is on the front or rear wheel! The bigger the human body over the riding object, like pushbikes, the more you can do with your weight!

The steering in and running wider is easy explained by the centre of gravity! When the weight is inside the corner, like motogp rider hang of the bike, the cog is lowered. Put the rider on the outside of the bend, like supermotard riders do, the cog will be higher!

When you tinker further about this you can see why supermotard riders are less prone to highsiding! The centre of gravity is much closer to the point where the whole is balancing on. And that way it's harder to tip over when the balancing point starts to move (slide). It's a bit difficult to explain but I think you lot can!

I love it that there are people like you who think about stuff like this :hail They are hard to find!
 

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Heck, I'll crack on about the TLR's weight distribution as well! Some must have heared the TLR does well with extra wheelbase! I'm not sure, but probably the yoshi TLR had a different swinger partly for that.

When you look at the TL there is quite some weight on the rear end. The stock cans weigh 16kg alone! And they are so far back, so far away from centre of gravity, that they have quite some leverage on the bike (cog)! What has the latest and greatest from Japan tought us? Centre of gravity as compact as possible! Now maybe those cans are not the problem, but there is nothing to balance it out! At one point I've put the front and the rear wheel on a weighing scale (?) and even with lighter cans the rear was heavier, if I'm not misstaking. And that was without a rider! And you all know where the rider will come etc etc!

This is partly the reason I'm building up the TLR again (after abandoning the project about a year ago). I want to make it better, I want to put the theories to the test :pirate
 

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Loki, a V-Twin bike has weight bias issues because of the engine configuration. A single pot out the front of it. The TL engine heads have the exhaust cams set lower than the inlets so they could get the engine as far forward as possible and leave wheel and radiator clearance.

Honda put the VTR radiators on the side.
 

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Never knew about the head design! Great stuff! :thumbup

But I still believe the exhaust design is really not helping on the so called running wide problems etc!
 
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