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Old Skool
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Discussion Starter #1 (Edited)
Who makes high-low rear hubs? I recommended use of one in the thread below regarding loose drive side spokes. However, now that I have spent some time poking around it seems that they are hard to find. Chris King “classic” hubs are a high-low design. Are there more that are available? Phil Wood used to make them (long long ago in a galaxy far far away), but there are none currently listed on their website.

Given the extreme amount (by old school standards) of dish necessary in wheels using a modern 10 speed freehub, I am surprised that the major manufacturers like Campy and Shimano do not offer a high-low design. Does anyone care to comment on this?

As background, “high-low” refers to a hub with a larger drive side flange than the non drive side. This works to equalize (between the two sides of the wheel) the angle at which the spokes leave the rim and effectively reduces the need to have the drive side at a greater tension. This, in turn, allows you to increase the tension on the non-drive side and still maintain proper dish. All else being equal, the end result is a wheel that is stronger than one built with a conventional hub.
 

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wheelbuilder
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Stogaguy said:
Who makes high-low rear hubs? I recommended use of one in the thread below regarding loose drive side spokes. However, now that I have spent some time poking around it seems that they are hard to find. Chris King “classic” hubs are a high-low design. Are there more that are available? Phil Wood used to make them (long long ago in a galaxy far far away), but there are none currently listed on their website.

Given the extreme amount (by old school standards) of dish necessary in wheels using a modern 10 speed freehub, I am surprised that the major manufacturers like Campy and Shimano do not offer a high-low design. Does anyone care to comment on this?

As background, “high-low” refers to a hub with a larger drive side flange than the non drive side. This works to equalize (between the two sides of the wheel) the angle at which the spokes leave the rim and effectively reduces the need to have the drive side at a greater tension. This, in turn, allows you to increase the tension on the non-drive side and still maintain proper dish. All else being equal, the end result is a wheel that is stronger than one built with a conventional hub.
It doesn't work that way, but in answer to your question:

White Industries
Tune

Just two off the top of my head.

-Eric
 

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Old Skool
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Discussion Starter #3 (Edited)
Please enlighten me...

ergott said:
It doesn't work that way,
OK please enlighten me, how does it work? I'll admit up front that I am not an expert in these matters
 

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wheelbuilder
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Stogaguy said:
OK please enlighten me, how does it work? I'll admit up front that I am not an expert in these matters
High low flange hubs are easier to make lighter because the non drive flange is smaller. The drive flange is larger, which is a benefit because it increases the spoke angle a small amount. If you had both flanges the same large size it would be no different than if the nondrive was small. It would be just heavier. Since low flange is lighter, that is what is used.

The placement of the non drive flange is always a compromise. To far away from center and you have very low tensions. To close to center and you have a poor spoke angle decreasing lateral stiffness. You can achieve a balance between the two with a high or low flange.

-Eric
 

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high-low flange purposes

Stogaguy said:
OK please enlighten me, how does it work? I'll admit up front that I am not an expert in these matters
The ratio of the tension between right and left flange is controlled only by the angles of the spokes on either side. Increasing the diameter of the flange has only a very small effect on the angle of the spokes - moving the flanges left of right has a much larger affect on spoke angle. Also, the main limiter on the angle of the right spokes is clearance between the spokes and derailleur. Regardless of flange offset or diameter, you can't increase bracing angle of the right spokes beyond this limit. The appearance radially laced right spokes is partially a result of this limitation - without the added "width" at the spoke crossing, the right flange can be moved outboard a few extra millimeters.

There are a variety of practical reasons for high-low flange hubs to exist. However, none of them have to do with equalizing spoke tensions. Here are a few:

1) Some freehub designs, especially those with oversized axles, have their pawl mechanisms located inboard of the freehub body, under the right flange. This necessates a large right flange, to make room for the pawl mechanim.

2) Dished rear wheels often require slightly longer spokes on the left side. Phil Wood made a high-low hub with a slightly larger left flange, so that both sides of the wheel used the same spoke length, reducing the number of spare spokes to be carried on tour.

3) For single sprocket applications (single speeds and fixed gear wheels), a larger right flange makes spoke replacement easier as the sprocket need not be removed to replace the spoke.

It used to be believed that a larger flange transmitted torque better. However, further analysis and measurements have found that there is no improvement in torque transfer between larger flanges and smaller flanges.
 

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wheelbuilder
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Mark McM said:
2) Dished rear wheels often require slightly longer spokes on the left side. Phil Wood made a high-low hub with a slightly larger left flange, so that both sides of the wheel used the same spoke length, reducing the number of spare spokes to be carried on tour.
My current Phil Wood 9 speed (I have a Dura Ace 10 cassette on) has the larger non drive flange. The spoke length is different enought to warrant two different spoke lengths (1.2mm different). In theory it is a grea idea, but it didn't end up this way for me.

-Eric
 
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