My stoker and I have ridden over 11,000 miles (mostly randonneuring miles in hilly/mountainous terrain) with 9-speed indexed (bar-end) shifting (Deore RD), a Sugino 24/36/48 crankset and SRam 11x34 cassette. The 48-11 combo is high enough, once you get over 30 miles an hour you may as well tuck. The 24-34 is low enough for almost any grade you'll encounter. I never have problems with downshifts, but for upshifts have to shift slightly past the "click" wait until I hear/feel that the derailleur has shifted then let the shift lever fall back to the click. I suspect that you may have some cable drag, but it may also be that you've optimized the shifting for upshifts and that's making it "hang" on the downshifts.
Nick On Tuesday, June 21, 2016 at 8:48:46 AM UTC-4, Michael Hechmer wrote: > > I was really optimistic about this and worked hard at it, even had stoker > Pat with her quilters eye confirm my alignment. It didn't change the > outcome. Then I measured the chain and found it at .75, so cleaned up the > rings, cogs, & pulleys and then put on a new chain. This helped. Now when > I drop down from the largest cogs it simply hesitates until I put a tad > more pressure on the shifter. When I get down to the middle of the > cassette, it starts to work perfectly. I am considering trying a new > cassette but would need to buy one and since I have been thinking about > moving to 10 speed, hesitate. > > As I posted on the tandem discussion "tandems create the worst possible > case for shifting. They have long cables that stretch a lot; the captain > & stoker may have difficulty coordinating pedal pressure during shifting; > they require a higher hi gear because its easy to spin out and they require > a lower low gear because they don't climb as effectively as a single. > Finally the captain and stoker often prefer different cadences making big > jumps between gears hard to satisfy both riders." So in order to solve > some of these problems I am thinking about moving from a 9 speed 48/38/26 & > 11/28 to a 52/38/28 with a 10 speed 11/30 or 32. > > Michael > > On Monday, June 20, 2016 at 6:20:32 PM UTC-4, Joe Bernard wrote: >> >> As you're looking at the bike from behind, your derailer pulleys are >> lined up slightly to the right of the center of each cog. In this position >> you'll get a clean shift to the left towards bigger cogs, but as it moves >> to the right towards smaller, the chain wants to skip too far right to the >> next smaller cog. >> >> What you want to do is get the chain/derailer/pulleys under the middle >> cog, then adjust until everything is directly lined up, or possibly even >> slightly biased to the left. If your derailer has an adjuster thingy where >> the cable enters derailer, turn it counterclockwise to slightly budge those >> pulleys leftward. If not you'll need to mess with the cable anchor until >> you have things where you need them. >> >> Hopefully this all makes sense. Good luck! >> >> -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
