keevon
10-24-2011, 04:23 PM
I wanted to document this project for posterity. Check back as it unfolds!
Back story: I managed to strip the threads off both sides of my Nashbar track hub in the space of a few months. One set of stripped threads was my fault: I neglected to re-tighten the lockring a few days after installing a new cog. The second set somehow stripped after the chain popped off on a very steep downhill. Regardless of how it happened, I have lost faith in threaded track cogs.
The solution is to build a new rear wheel with a converted MTB disc hub. This idea has been around for a few years, but for some reason it hasn't caught on more: (pics from Velo Solo)
http://www.velosolo.co.uk/pictures/dscn4374a.jpg
http://www.velosolo.co.uk/pictures/dscn4398a.jpg
I'm using a Shimano Deore XT M-756 front disc hub. This hub has symmetrical flanges, a 6-bolt disc mount, loose-ball bearings (preferred for routine overhauls), and pretty good seals. A Wheels Manufacturing 10x1x137mm quick release axle, 20mm of axle spacers, and a Velo Solo 3/32" x 17 tooth cog are the parts necessary for the conversion. The axle will be cut down to 130mm so I can use it on my 120mm-spaced Steamroller (a Surly Tuggnut allows me to use a quick release on my fixed gear). This will all be laced into a Salsa Delgado Cross rim.
Converting the disc hub should be simple: disassemble the hub, replace the 110mm axle with the 130mm axle, re-install the cones, install new axle spacers (15mm on non-drive side, 5mm on drive side), and re-install locknuts. After building the wheel, the new cog simply bolts on with 6 disc rotor bolts.
Here are the anticipated dimensions of the converted hub:
Over-locknut dimension: 120mm
Flange diameter: 61mm
Center to left flange: 26.1mm
Center to right flange: 26.7mm
Chainline should be 46mm, which matches perfectly with the outer position on a road crank.
I'll post step-by-step photos once everything arrives. Thanks for looking!
Back story: I managed to strip the threads off both sides of my Nashbar track hub in the space of a few months. One set of stripped threads was my fault: I neglected to re-tighten the lockring a few days after installing a new cog. The second set somehow stripped after the chain popped off on a very steep downhill. Regardless of how it happened, I have lost faith in threaded track cogs.
The solution is to build a new rear wheel with a converted MTB disc hub. This idea has been around for a few years, but for some reason it hasn't caught on more: (pics from Velo Solo)
http://www.velosolo.co.uk/pictures/dscn4374a.jpg
http://www.velosolo.co.uk/pictures/dscn4398a.jpg
I'm using a Shimano Deore XT M-756 front disc hub. This hub has symmetrical flanges, a 6-bolt disc mount, loose-ball bearings (preferred for routine overhauls), and pretty good seals. A Wheels Manufacturing 10x1x137mm quick release axle, 20mm of axle spacers, and a Velo Solo 3/32" x 17 tooth cog are the parts necessary for the conversion. The axle will be cut down to 130mm so I can use it on my 120mm-spaced Steamroller (a Surly Tuggnut allows me to use a quick release on my fixed gear). This will all be laced into a Salsa Delgado Cross rim.
Converting the disc hub should be simple: disassemble the hub, replace the 110mm axle with the 130mm axle, re-install the cones, install new axle spacers (15mm on non-drive side, 5mm on drive side), and re-install locknuts. After building the wheel, the new cog simply bolts on with 6 disc rotor bolts.
Here are the anticipated dimensions of the converted hub:
Over-locknut dimension: 120mm
Flange diameter: 61mm
Center to left flange: 26.1mm
Center to right flange: 26.7mm
Chainline should be 46mm, which matches perfectly with the outer position on a road crank.
I'll post step-by-step photos once everything arrives. Thanks for looking!