Wheel lateral stiffness. WHat makes it stiff?
#1
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Wheel lateral stiffness. WHat makes it stiff?
Not sure I understand bike wheels.
What makes a wheel stiff?
Is it the spoke tension?
Spoke diameter?
rim width?
or what???
details please
Can you improve on a wheels lateral stiffness? How?
thanks
What makes a wheel stiff?
Is it the spoke tension?
Spoke diameter?
rim width?
or what???
details please
Can you improve on a wheels lateral stiffness? How?
thanks
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Probably all of the above. Did you mention spoke count?
I would think spoke tension would be primary.
The rim will deform somewhat under your weight, and de-tension the lower spokes somewhat. So, a deep profile rim might also be a little stiffer than a low profile rim.
I would think spoke tension would be primary.
The rim will deform somewhat under your weight, and de-tension the lower spokes somewhat. So, a deep profile rim might also be a little stiffer than a low profile rim.
#3
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Spoke angle from wider hubs.
Fewer crosses.
A heavier spoke probably adds a very slight amount.
Fewer crosses.
A heavier spoke probably adds a very slight amount.
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It is the constituent parts, and how well the wheel builder can work them.
You can take the best parts around, and make a floppy wheel if you don't know what you are doing. A spoked bicycle wheel is stiff fundamentally because of the large amount of tension in the spokes.
You can take the best parts around, and make a floppy wheel if you don't know what you are doing. A spoked bicycle wheel is stiff fundamentally because of the large amount of tension in the spokes.
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It is the constituent parts, and how well the wheel builder can work them.
You can take the best parts around, and make a floppy wheel if you don't know what you are doing. A spoked bicycle wheel is stiff fundamentally because of the large amount of tension in the spokes.
You can take the best parts around, and make a floppy wheel if you don't know what you are doing. A spoked bicycle wheel is stiff fundamentally because of the large amount of tension in the spokes.
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That's not very detailed. What unit of measure would you use for the quantity of "resistance?"
For design purposes, more useful quantities include elasticity, strain, stress, deformation, section modulus, etc, all of which have specific definitions and units of measure.
For design purposes, more useful quantities include elasticity, strain, stress, deformation, section modulus, etc, all of which have specific definitions and units of measure.
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That's not very detailed. What unit of measure would you use for the quantity of "resistance?"
For design purposes, more useful quantities include elasticity, strain, stress, deformation, section modulus, etc, all of which have specific definitions and units of measure.
For design purposes, more useful quantities include elasticity, strain, stress, deformation, section modulus, etc, all of which have specific definitions and units of measure.
Congrats.
IF you will define them, I will select one.
AS I commented earlier, which ever one prevents the rim at the top from rubbing the brakes.
Otherwise, for each, define how to improve that metric
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A modicum of brake pad clearance, plus the fact that the force you put on your wheels is generally "straight down" even when you're banking into a turn.
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How much do you put?
And yes, I do pull out the feeler gauges.
If it is not flex, what could cause it?
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On a standing hill climb, however, forces may deviate somewhat from the wheel axis.
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A wheel out of true could cause a periodic brake rub. Or, effectively reduce the clearance significantly.
1mm out of true.
1mm clearance.
And suddenly you have essentially zero clearance. Even if not rubbing on the stand, the slightest perturbation and it will pulse.
1mm out of true.
1mm clearance.
And suddenly you have essentially zero clearance. Even if not rubbing on the stand, the slightest perturbation and it will pulse.
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Oh, they do flex. No one can argue that. I'm just saying why it generally isn't more than a mm or two for normal riding. If your wheels are true, with adequate tension, perhaps you just need to add a little more brake pad clearance.
#21
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Left out hub flange width and diameter .. a IGH or proper track rear hub is stiffer laterally because it is un dished
lacks the tension imbalance needed to pull the rim to the right
to make room for all those 'speeds' in a cassette
and the hub flanges are further apart.. flanges of the front hub are wider apart than a cassette Rear..
lacks the tension imbalance needed to pull the rim to the right
to make room for all those 'speeds' in a cassette
and the hub flanges are further apart.. flanges of the front hub are wider apart than a cassette Rear..
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#24
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The issue isn't flex at the top of the wheel because all of the weight of the bike is essentially standing on the spoke at the bottom of the wheel.
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I didn't read all the answers above, so apoligies for duplicate info.
wheel stiffness depends almost entirely on the total amount of steel, namely the cross section X the no. of spokes.
Shorter spokes also increase stiffness, but the difference isn't great because the difference between the shortest (radial) and longest spokes possible is very small.
Rim lateral stiffness is also a factor, especially if spoke counts are lower, because stiffer rims spread the load more, bringing more spokes into play.
Then other factors come into play, including flange separation and spoke hole offset in rims, which affect the bracing angles & whether the spokes are woven over/under at the cross.
However TENSION HAS NO EFFECT ON STIFFNESS.
wheel stiffness depends almost entirely on the total amount of steel, namely the cross section X the no. of spokes.
Shorter spokes also increase stiffness, but the difference isn't great because the difference between the shortest (radial) and longest spokes possible is very small.
Rim lateral stiffness is also a factor, especially if spoke counts are lower, because stiffer rims spread the load more, bringing more spokes into play.
Then other factors come into play, including flange separation and spoke hole offset in rims, which affect the bracing angles & whether the spokes are woven over/under at the cross.
However TENSION HAS NO EFFECT ON STIFFNESS.
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.