Old 06-06-20 | 12:09 PM
  #16  
fietsbob
Banned
 
Joined: Jun 2010
Posts: 43,586
Likes: 1,380
From: NW,Oregon Coast

Bikes: 8

Originally Posted by rscott67
Made up my mind. Bought a vybe D7 a couple of years ago. Modified to a killer 11sp. Currently sporting a Single 52t front chainring. Going to move to a double. Decided on doing a 56t/40t 130BCD 170mm configuration. #1 . will my shifting be horrid with the tooth jump? #2 . Large chainring diameter on 56t-should I just stick to 53/39 standard and play it “safe?” And of course, I’ve only got 20” wheels.
If you use 'greasy finger shifting'.. No Problemo, you put the chain on the other chain ring with your fingers while Stopped../
then at the top of the hill you put it back on the big chainring.. ?

A Schlumpf speed drive has a 1.6x internal gear, so in overdrive a 34t acts like a 54t
because the crank arms are on one side of the gears chainring on the other
Physical 39t acts like a 62 t as chainring turns faster than the crankarms..

http://www.schlumpfdrive.com/index.php/home-en.html

..

Last edited by fietsbob; 06-06-20 at 12:20 PM.
fietsbob is offline  
Reply