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Better quality rear axle for 6 speed

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Better quality rear axle for 6 speed

Old 06-23-23, 12:32 PM
  #51  
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Originally Posted by smd4
Why would anyone ever want to add these to a bike??
For me is touring and leisure long distance. My back has about 60 miles on it before I have to start riding all over my handlebars. On a loaded trip I may spend more time on the top than on the drops.

Heck if you look at the picture you'll notice that the handlebars are pretty much at the same level as the seat. On leisure distance I spend a lot of time with my hands on the bar ends in a still pretty upright position. If I was riding in a group at group drifting speeds the stem would go way down so I could be on a more aero position.

Last edited by abdon; 06-23-23 at 02:35 PM.
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Old 06-23-23, 01:51 PM
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Originally Posted by icemilkcoffee
Of course the fulcrum point would remain the same. The fulcrum point being the bearing. What is changed, with a long nosed cone, is that the bending point would be moved inwards. When you move the bending point inwards away from the fulcrum point, there is now less leverage to bend the axle.
In other words, you are reinforcing the axle (with a threaded sleeve), right where it is most likely to bend.


The fulcrum(pivot) point is the ball bearing. The F is where the frame drop out is. The W is where the bend occurs. When you move W out further away from the pivot point, guess what, it takes more force to bend the axle.
I knew it was something like that.
Understanding it is one thing, clearly explaining it as you did are completely different things.
That being said, I think you misunderstand what I was saying.
EDIT:
I said that a longer cone will not help to alleviate the bending of axles on a freewheel hub.
Reason being is the fulcrum point being the internal edge of the cone from the drop out on the drive side. the longer cone is not changing the fulcrum point.
Cassette hubs don't bend axles like freewheel hubs because of the bearings being further abart.
Notice I didn't say they don't bend axles, just that it's different and not quite as bad.

Last edited by Schweinhund; 06-23-23 at 02:40 PM.
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Old 06-23-23, 10:05 PM
  #53  
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Originally Posted by icemilkcoffee
If axles are always bending right behind the cone, then why don't they make the cone longer? ie. extend out the nose of the cone? It's such an obvious solution I'm surprised nobody came up with it except me,
How long were you thinking?
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Old 06-23-23, 10:14 PM
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Originally Posted by abdon
I don't foresee having any issues, I don't plan on loading this bike all that much nor riding it all that hard. All I was asking about was for a quality part mostly out of principle, I'm happy with the Wheels Manufacturing axle I just got..
Back in the day, all my Normandy and Zeus hubs got Campagnolo axle-cone sets, partly because they fit and partly because they were stronger and smoother. When that stuff disappeared I always went to the Wheels Mfg catalog first.
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Old 06-24-23, 04:56 AM
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Originally Posted by icemilkcoffee
Of course the fulcrum point would remain the same. The fulcrum point being the bearing. What is changed, with a long nosed cone, is that the bending point would be moved inwards. When you move the bending point inwards away from the fulcrum point, there is now less leverage to bend the axle.
In other words, you are reinforcing the axle (with a threaded sleeve), right where it is most likely to bend.


The fulcrum(pivot) point is the ball bearing. The F is where the frame drop out is. The W is where the bend occurs. When you move W out further away from the pivot point, guess what, it takes more force to bend the axle.
You might want to actually read the links I posted. The DS dropout is not where the force causing the bending moment on a freewheel rear axle is applied. Rather, it's applied at the rear sprockets during pedaling.

In the real world, nothing is of infinite stiffness; everything deforms when subjected to force. This is true of wheel axles, bearings, races, hub bodies . . . you name it. All of these deform (flex) when force is applied. Plus, bearing lube partially displaces.

Repetitive deformation (flex) of the cantilevered end of the axle (e.g., the part between the inner bearing cone end and the point at which the force causing flexing is applied) due to forces applied by pedaling - coupled with axle threads acting as a stress riser - is what causes axle failure at the inner end of the DS cone. It's the worst on a freewheel axle because these have the longest cantilevered portion between point of application of force and point of maximum stress on the axle.

Again: the late Mr. Brandt knew both engineering and bicycling - likely far better than you and I combined. His analysis in this case appears sound.

Last edited by Hondo6; 06-24-23 at 05:16 AM.
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Old 06-24-23, 07:35 AM
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Originally Posted by Dave Mayer
Go to your local bike Co-op where they will have a bucket-o-axles in every weird size and length possible. We do. We sell them for $1 used and $5 for new fancy ones. Make sure the used ones roll straight.

We have dozens of 145mm long 10mm hollow axles for rear quick-release hubs, the most common size. If 145mm is too long, then 5 minutes with a hacksaw fixes it.

No Co-op? Then beg and scavenge the parts from the wrecked wheel collection at the back of you local shop. This is one of the reasons why Shimano hubs are so great: spare parts everywhere.
I've only had one bent axle, and a few minutes looking through their parts bin at my LBS was all it took.
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Old 06-24-23, 07:46 AM
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+1 on Wheels Manufacturing, but as Dave said, check with your local LBS or Co-op first.

Yes, we all know that this configuration is more prone to bent axles, but that doesn't mean they all bend. I've had plenty of bikes with 6-speed freewheels, have ridden many thousands of miles on them, and the only bent axle I've encountered was that way when I bought it. It was an easy replacement and it's been fine ever since. I'm with you on not wanting to buy a $10 Chinese-made axle.
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Old 06-24-23, 10:30 AM
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Originally Posted by Hondo6
You might want to actually read the links I posted. The DS dropout is not where the force causing the bending moment on a freewheel rear axle is applied. Rather, it's applied at the rear sprockets during pedaling.

In the real world, nothing is of infinite stiffness; everything deforms when subjected to force. This is true of wheel axles, bearings, races, hub bodies . . . you name it. All of these deform (flex) when force is applied. Plus, bearing lube partially displaces.

Repetitive deformation (flex) of the cantilevered end of the axle (e.g., the part between the inner bearing cone end and the point at which the force causing flexing is applied) due to forces applied by pedaling - coupled with axle threads acting as a stress riser - is what causes axle failure at the inner end of the DS cone. It's the worst on a freewheel axle because these have the longest cantilevered portion between point of application of force and point of maximum stress on the axle.

Again: the late Mr. Brandt knew both engineering and bicycling - likely far better than you and I combined. His analysis in this case appears sound.
In fact Brandt said exactly the same thing I said. From Brandt's article:


He places the w right where I said it was- just behind the cone. Therefore extending the cone in that direction, would move that w point further away from X, which is the pivot point. Hence less leverage. And that is the case whether you think the bending force is coming from the sprocket or the DS dropout. What exactly is your objection here?
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