-
Just a thought on tandem gearing
Tandems are fast on flat roads and downhill, but uphill they are a struggle (honking requires skill!). So for most non - racing purposes a low bottom gear is necessary.
I have a bike with a Cyclo 3 speed and I have tried and failed (so far) to find a sensible block. The largest sprocket I've got so far is a 21, but that comes with 3 tooth differences (16 - 19 -21). More common is 16-18-20, but what I'd prefer would be 16-18 and at least 22, and that's on a solo. I've overcome this by using a small inner ring, but this is not possible on a tandem without a crossover drive, which would, I think, be too modern for what you are aiming at.
A possible answer might be to combine your Cyclo with a Sturmey hub, which would give a further 25% reduction. I believe 22 tooth sprockets do exist for the standard 3 spline fitting.
Using a 3 speed mech. with only two sprockets may prove tricky, but would be possible.
clubman-
Ah, I like the idea of the combi SA and block but I’d need two shifters which could work as the Cyclo I have in the post is band on and the TT has a brazed fitting also? And I think I’ve seen a rear hub brake wheel with a SA and a sprocket on eBay. Hmm.
-
And the chainset I’m bidding on has a rear inner 46 ring, and if then combined with jeff80’s block at 20 with the SA makes it all pretty close to what you’re suggesting?
crossedthread
Just brought that from the link, looks exactly right, thanks very much :)