Rainy here yesterday, so I got me to fettlin'.
I want to put thumbshifters on my '92 Stumpjumper Comp.
http://www.retrobike.co.uk/forum/viewto ... 2&start=30
I put the thumbies on, and they look very nice just sitting there on the bars, but they probably need to be connected to something. So, on with the mechs.
I'd planned to run 2x8 with eight ninths of a 9-speed 11-32 cassette, leaving the 11 off, and 42 29 at the front, friction shifting.
The rear hub's a Phil Wood cassette hub that came from eBay years ago. I've been running it with spacers and a single DX BMX sprocket since then, but I'd assumed it would take a 7-speed (and therefore eight ninths of a nine speed) cassette. It doesn't. The splines aren't quite long enough, and with the lockring snugged down, the 12 doesn't have any engagement.
Plan B: a dished Ritchey 33t 2x9 sprocket, then build up the rest of the cassette with loose sprockets. No go: the tolerances don't match, and the Ritchey sprocket won't fit the Phil hub.
So, what to do? I could use 7 8-speed sprockets, but I want the 12 and the 32, and that means bigger jumps than I'm happy with. I could go triple at the front, and run a 12-24 8-speed spaced 3x7, but I'd need a longer bottom bracket and I like the low Q of my 103mm WTB Greaseguard unit. I could probably get someone to machine a couple of millimetres off the back of the cassette spider, but the Mavic rear mech already comes pretty close to the spokes, and I'd rather not tempt fate. I could build up a new wheel with an old XT 7-speed hub, but I've got more than enough wheels kicking around, and the Phil suits the bike very well.
One idea that came to me is that maybe somebody makes a 12 and 14 tooth combo 9-speed double sprocket machined in one piece with splines running the full length of the unit. That would get me the spline engagement I need. Anyone ever heard of such a thing?
Any other ideas?
Calmes dans le demi-jour
Que les branches hautes font,
Pénétrons bien notre amour
De ce silence profond.