I've got two road racing bikes. On one of them the back of the bike feels like it's going to washout when I'm cornering really hard -- I have to consciously sit firmly in the saddle with my weight back to feel secure. The other feels more secure when cornering hard whereever I am in the saddle.
The more secure bike has slightly longer chainstays, and I'm wondering if that helps the feeling of security. But the bikes differ in other ways too, so I am not at all sure what the difference is (though it's not the wheels/tires -- I share them between bikes).
Any thought about this? In particular, if all else was equal do longer chainstays get more or less weight over the rear wheel?
<I've got two road racing bikes. On one of them the back of the bike <feels like it's going to washout when I'm cornering really hard -- I <have to consciously sit firmly in the saddle with my weight back to <feel secure. The other feels more secure when cornering hard <whereever I am in the saddle. < <The more secure bike has slightly longer chainstays, and I'm wondering <if that helps the feeling of security. But the bikes differ in other <ways too, so I am not at all sure what the difference is (though it's <not the wheels/tires -- I share them between bikes). < <Any thought about this? In particular, if all else was equal do longer
There have been discussions on chain stay length recently, I'd recommend google for that but what I though about was your headsets. I've been on badly handling bikes that just needed headset adjusttments.
all the best-c.p.
<chainstays get more or less weight over the rear wheel? < <JT
All else being equal, longer chainstays remove weight from the rear wheel. Basic physics, center of mass, weight distribution. ALL ELSE BEING EQUAL
How so, and what do you mean by "all else being equal"? Since weight is taken up by the two contact patches both wheels have with the ground, what does it matter that the bike has a longer wheelbase? The weight distribution is still the same.
All else being equal, longer chainstays remove weight from the rear wheel. Basic physics, center of mass, weight distribution. ALL ELSE BEING EQUAL
How so, and what do you mean by "all else being equal"? Since weight is taken up by the two contact patches both wheels have with the ground, what does it matter that the bike has a longer wheelbase? The weight distribution is still the same.
Not if that longer wheelbase is achieved by lengthening the chainstays, moving the back wheel out from under the rider.
Consider an extreme case; shorten the chainstays until the seatstays are straight up and down. Now _all_ the rider's weight is on the back wheel (which won't turn because it interpenetrates the seat tube and downtube, but never mind that. :-) -- David Damerell <[email hidden]> Distortion Field!
All else being equal, longer chainstays remove weight from the rear wheel. Basic physics, center of mass, weight distribution. ALL ELSE BEING EQUAL
Jose Rizal said:
How so, and what do you mean by "all else being equal"? Since weight is taken up by the two contact patches both wheels have with the ground, what does it matter that the bike has a longer wheelbase? The weight distribution is still the same.
No, if you extend the chainstays, without moving the center of mass of the bike/rider, the weight load on the rear wheel will be lessened, while the weight load on the front will be increased by the same amount.
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All else being equal, longer chainstays remove weight from the rear wheel. Basic physics, center of mass, weight distribution. ALL ELSE BEING EQUAL
Jose Rizal said:
How so, and what do you mean by "all else being equal"? Since weight is taken up by the two contact patches both wheels have with the ground, what does it matter that the bike has a longer wheelbase? The weight distribution is still the same.
No, if you extend the chainstays, without moving the center of mass of the bike/rider, the weight load on the rear wheel will be lessened, while the weight load on the front will be increased by the same amount.
Exactly. I suspect the effect is quite minor. But perhaps I should not guess. Naw, finding out requires setting up (time) the measuring system and we all know the usenet is not about substance anyway.
I've got two road racing bikes. On one of them the back of the bike feels like it's going to washout when I'm cornering really hard -- I have to consciously sit firmly in the saddle with my weight back to feel secure. The other feels more secure when cornering hard wherever I am in the saddle.
Quoted message said:
The more secure bike has slightly longer chainstays, and I'm wondering if that helps the feeling of security. But the bikes differ in other ways too, so I am not at all sure what the difference is (though it's not the wheels/tires -- I share them between bikes).
Ideally your CG should be between the wheels and if you have ridden a tandem, you will recall that long bicycles corner more stably than short ones. However, sitting firmly in the saddle is not the ideal way to corner hard, but rather by unloading the saddle and using the legs as shock absorbers while maintaining some saddle contact. Sidewalls or cheeks of saddles help in this respect, something modern saddles eschew in favor of light weight.
Get off the saddle! The rougher the pavement the higher you'll need to get.
