At 07:04 PM 1/20/2005, mg@formlos.ch wrote:
>I recently bought a very nice dura ace HF track hub on ebay.
>when i got it i wondered why i couldn't fit custom 1"37 track sprockets on
>it. even my local bikeshop couldn't help. it has a stepped thread of 33x1 mm
>for the cog and 32x1 (left thread) for the lockring. i finally remembered
>shimanos revolutionary 10 pitch system launched in the 80s and found it in a
>old shimano catalog. the idea of10 pitch was obviously saving weight by
>smaller dimensions (10 mm chain links instead of 1/2"). it didn't survive
>for long since it was subsequently banned by UCI for racing. shimanos dating
>code says "CI" which stands for september 78. i didn't know they date back
>so far? i thought it came up only 81 or 82?
I'm posting this to the whole list in case anyone else has these hubs.
This happened to a young lady I know. But she didn't find out standard cogs wouldn't fit till after she'd built up 2 wheels using the hubs. I was able to find a CNC machinist to make her a couple of 1/2" pitch cogs with the right threading. I assume he saved the program.
He only charged $20 each, but now that he's made some he may think he underbid. I imagine you would get his best price if you want the same # of teeth as Sara did.
If you are interested in pursuing this, let me know.
Mark Stonich
Minneapolis Minnesota
http://bikesmithdesign.com
http://mnhpva.org