Three Speed MTB

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The Good Choice

Bontrager offers a hub identical to the $35 hub described below. It cost $79.99. 430g. P/N #271412. (The Bontrager SS hub & the Nashbar hub are made by Formula. Both hubs are sold under various other brand names.) It is different in two ways:

  • Drilled for 32 spokes
  • Quick release

This solves many of the problems with the $35 for a bit more money. In retrospect, I should have used this hub.

The $35 Hub

This hub is offered by several companies at various price points. It is a essentially a Formula BX-2210 BMX Cassette Hub with 135mm spacing and an upgrade to cartridge bearings. It can also be found as a Novatec (Joy) D256SBT. Other companies branding it under their own name are Woodman, Planet-X (On-One), IRO, and Bontrager. Many others may exist, but the cheapest one I was able to find was the Nashbar NF-SSHR. Cost $34.95. That is CRAZY cheap.

One Problem. The hub is drilled for 36 spokes. This is bad. 32 spokes is standard, so this makes parts inventory difficult. It also drives the weight up.

The Nashbar hub includes a sprocket which some of the other companies neglect to include.

Internal parts


Two bearings in the cassette body. Quality.



Converting to Quick Release

The hub comes set up with a bolt-on axle. Pretty lame by modern standards. It needs to be converted to quick release and do on a serious diet. The solid axle is a literal boat anchor.

A generic quick release axle for this hub would be 146mm wide with a 10X1mm thread. Since this is a special axle type, a replacement must be sourced from a similar hub spare parts list.

Since Bontrager is now using this hub in both itterations, #250795 Bolt-on and #271412 Quick Release, we can source parts through the local Trek dealer. Quick release axles for it, #SP-271397-TRE, can be ordered for $20.

The Bontrager hub is in fact, not compatible.


The Bontrager hub retails for $79.99. It's a good price, but we can make that cheaper. Our total hub cost with new axle is now $54.95. Nice.

Gearing The Cassette

Since 8 speed lockrings with cogs integrated on them are available, it is best to construct the cassette with 8 speed spacing. The cassette lockring is a standard ISO 1.375x24T right hand thread lockring. Same as old school bottom brackets. I replaced the cheapo one with a nice old Suntour version that I had in stock.

I had a few 9 speed cogs laying around to construct this mock up. Make sure to use cogs with shift ramps if you possibly can.



A 15-18-21, nine speed spaced, 3 speed cassette.

Four Speed?

A Uniglide threaded cog, if you can find one (8spd), at the end of the cassette might be used instead of the lockring to make this into a four speed cassette. This has not been proven yet, but it may be possible.

Since Uniglide parts are almost extinct, two options still exist:

  • Surly makes Track Cogs. They are threaded at ISO 1.375x24tpi and come in two widths, 3/32" (8spd) and 1/8" (1spd). They are also available in tooth options from 13 to 22.
  • Shimano Dura-Ace Track Cogs are commonly available in 13 to 16 teeth in both 3/32" and 1/8" widths.

I ordered a 14t Surly cog to see if I could make a 14-19-24-30 cassette.


With the cassette described above and a small spacer on the back side of the cassette, the chainline for this rear end comes to 48.5mm. Quite narrow, but possible using some extremly short square taper bb's.

Zero Dish?

The wheelbuilding info on this hub is as follows:

  • Diameter of Hub at spoke hole circle: 58mm
  • Right (drive side) center of hub to flange: 34mm
  • Left(brake side) center of hub to flange 38mm
  • Diameter of individual spoke holes: 2mm

So, the dish is off by 4mm and spoke length works out to be 262mm (left) and 261mm (right) when 3 crossing a Mavic XM321 rim.

This is fine. At least the spaceing erred on giving a wider hub flange spacing, 72mm. That is almost 6mm wider than my Hadley single speed hub (66.4mm).

This is going to make quite the bomber wheel.