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Old 11-24-16, 04:13 PM
  #23  
bulldog1935
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Join Date: Jul 2016
Location: downtown Bulverde, Texas
Posts: 2,717

Bikes: '74 Raleigh International utility; '98 Moser Forma road; '92 Viner Pro CX upright

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If you're going to mostly keep it on pavement, here's the 7-sp (freewheel) cyclotouriste triple on my '74 Raleigh Interational (this was on my '77 Raleigh Grand Prix from college for four years before I crashed the frame). Rear axle is 126mm - both Raleigh frames were 120mm rear axle and the rear triangles realigned to take the 126mm axle.
This is basically the same gearing as the compact double on the Viner, but a little more complicated using older hardware. 32mm tires are the biggest that will fit the rear triangles.
(Also possible to find 126mm cassette hubs for 7-speed - I did this because I got a good deal on the quality freewheel wheelset)
The triple is set up as half-steps + granny, the idea being the 2 big rings split the wide gear steps between the rear cogs, giving you narrow gear steps from end to end

This friction shifts (I'm using bar ends).
Suntour Cyclone GT RD, Suntour winner freewheel 12-30t; Shimano 600EX FD, Sun XCD crank arms with TA triple stack 46/42/26T.

The cyclotouriste triple crank requires a 122mm (ish) asymmetric BB which I did with a 121mm SKF bottom bracket using a 2.5mm spacer to make it asymmetric (there's also a 4mm spacer available if you need more chainstay clearance).


between the 3x7 half step triple and 2x9 wide compact double -
On the 2x9 wide compact double, you almost never shift up front except when you really need the granny to climb steep - then you have a gang of narrow low gears to match any grade.
On the 3x7 half-step triple, usually shift more often between the half steps and shift less often in the rear, but it's a lot of fun when you get used to it.

My algorithm for the half steps is get on the big ring as soon as you can and always shift first up front - first take the half step down to climb, then shift in the rear as you need it. Cresting the hill, again shift first to the big ring, then shift in the rear as you speed up. The little granny ring works the same way on either setup - a gang of narrow low gears.

But with either setup, you can always find a perfect gear for any grade with any load.

Last edited by bulldog1935; 11-24-16 at 05:38 PM.
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