Change from a single speed hub to 2 speed kickback

[PD Monkey]

I have a 60's S-7 wheel with a single speed Schwinn approved hub. I picked up a yellow band 2-speed hub that I want to replace it with. The current hub is 2.34" diameter, the yellow band is 3.4", the spokes are 10.5" long. So if I do the math, the new spokes should be 10" long. I did a google search (bicycle Heaven), it said the spokes should be 10.25" (S-7 and Yellow Band hub) long. I know I am not the first person to do this. Do I trust the math or the internet?

What are good spokes to rebuild with? Where is a good place to buy from? This is just a fun rider, not a restore.

TIA!

 

[ricobike]

10 1/4" is correct. Can't help you with where to buy them, I've picked up large lots of used spokes at swap meets and I just use those. For regular riding I would think any would work fine.

 

[Schwinn Sales West]

Sorry I'm not answering your question directly.

In a perfect world you want to find someone that has a Phil Wood spoke machine. They will take your order for the length of spoke you desire in metric. They set their machine to your desired length and the machine will cut to length and roll the new nipple threads onto a 14 gauge spoke blank. The quality of the new threads is 100%. It would take no more than five minutes to cut the 36 spokes you need for your wheel. The cut and threaded new spokes are stainless steel and will hold up great on a beach cruiser ridden around salty beach areas.

You want to use only 14-gauge spokes because they are straight, not swaged/butted like spokes that say 14/15/14. So, any straight, 14 gauge spoke that is longer than your new cut size will work. The Phil Wood machine was expensive, but any bike shop that built pro level wheels would have one. I have even threaded spokes as short as a couple of inches long for a restored Taylor Trike wheel.

Ask around, somebody here, or local to you has a old Phil Machine, it's a good solution to your spoke needs.

John

 

[GTs58]

My chart for the 2 speed specs out 10.25" also. That's with 3 cross.

 

[Archie Sturmer]

10.25 inches is about 260mm; (not sure if that would help in finding sources of supply).

The length of spokes is based primarily upon the law of cosines, (and somewhat upon a mere theory).
So, a 1” hub diameter change (e.g., 1/2” wider all-around) would be unlikely to result in a 1/2” spoke length change for 26” wheels.

 

[J-wagon]

The length of spokes is based primarily upon the law of cosines

Maybe this:

For wheels with crossed spokes (which are the norm), the desired spoke length is

where

• d = distance (mm) from the center of hub (along the axis) to flange,
• r1 = spoke hole circle radius of the hub,
• r2 = half of effective Rim Diameter (ERD), or the diameter the ends of the spokes make in a built wheel of the rim,
• r3 = radius of spoke holes in the flange,
• m = number of spokes to be used for one side of the wheel, for example 36/2=18,
• k = number of crossings per spoke, for example 3 and
• a = 360° k/m, for example 360°*3/18 = 60°.

 

[Schwinn Sales West]

Any shop that has a Phil Wood Spoke Machine would also have a Phil Wood Spoke Calculator.

It was simply a Scientific Calculator and two fiberglass fishing rods to help you measure the true rim diameter of the nipple seating. You simply entered the hub diameter, spoke count number, spoke cross, and rim diameter, and it spit out the required spoke length.

 

[coasterbrakejunkie1969]

@PD Monkey The proper spoke length is 10 .25 inches at 3 cross spokes are available on ebay both 10.25 and 260mm post in the wanted section a few members may have what you need.

 

[WillWork4Parts]

Maybe this:

For wheels with crossed spokes (which are the norm), the desired spoke length is
View attachment 1782382
where

• d = distance (mm) from the center of hub (along the axis) to flange,
• r1 = spoke hole circle radius of the hub,
• r2 = half of effective Rim Diameter (ERD), or the diameter the ends of the spokes make in a built wheel of the rim,
• r3 = radius of spoke holes in the flange,
• m = number of spokes to be used for one side of the wheel, for example 36/2=18,
• k = number of crossings per spoke, for example 3 and
• a = 360° k/m, for example 360°*3/18 = 60°.

...Or enter your specific measurements into a nifty spoke calculator that correctly does the math for you. You know, so you don't misplace any parentheses and end up ordering spokes 3 miles long.

 

[coasterbrakejunkie1969]

Or you can just use the 10.25 spokes at 3 cross that multiple members have used already. It is not Rocket Surgery