Originally Posted by maranen
Tkatzir - Thank you for your answers. I've been thinking of what you did, and I must admit it's beyond my comprehension. Best I can do is about 100km a day. The bike setup is important of course but I guess one could say that you are the strongest link there. I can't express myself well in English but as a Finn I could say:"Perkele poika minkä teit!".
EvilV - I examined the Merc crank and came to the same conclusion as you. I even experimented with an old 39 chain ring where I drilled holes to be able to fit it to the crank, but it didn't feel satisfactory for steepest hills. I'm writing this in an internet cafe and time is running out.
If you look carefully at this picture Maranen, you'll see what I mean. Check out the position of the chainring bolt you can just see through the frame at about the 11 o clock position. See how near the edge of the ring it is. I think you would definately require a different crank altogether to get a smaller ring.
Originally Posted by invisiblehand
Supposedly, the big cog on the SA-8 is too big for the Brompton's rear triangle.
If you look at BromptonTalk, you can find the details there.
Oh, the SA-8 has a ~300% range; much wider than the SA-3.
-G
Thanks for that. It's a pity, although I do like the simplicity and efficiency of the srf-3.