On Saturday, May 29, 2021 at 8:33:18 AM UTC-7 RichS wrote: > Couple things in Will's post that stood out for me: > > 1. Will said he wasn't happy with the way a Claris front derailer friction > shifted. I've used the Claris in double and triple configurations, friction > shifted (bar ends), 8 speed without any problems. Maybe I missing out on > something by not using a different der? I have a Suntour ARX on the way so. > . . >
Do you have the same version? Shimano reuses the same model name to differentiate their lineup, even if the actual derailleurs themselves have changed quite a bit throughout the years. For example, the 8-speed XTR from the 90s is a completely different beast than the Di2 XTR of today. >From visually examining the Claris called out in Will's email, it appears the incompatibility is due to cable pull. A longer arm will require more cable to move the cage the same distance, all things being equal. This won't matter at all for dedicated shifters (regardless of whether they're indexed), but friction shifters are generally designed for compatibility with older derailleurs, meaning they won't pull as much total cable as is required for the most current derailleurs. Examples of these are the 11 and 12-speed derailleurs, or SRAM's 1:1 actuation ratio derailleurs. Traditional friction shifters either can't pull enough, or pull barely enough cable to run the modern rear derailleurs. The same logic applies to front derailleurs with longer cable pull requirements. > 2. Wonder what the forthcoming "good" friction shifting derailers will be? > For me, ironically, good friction derailleurs will need to be matched to the cable pull capacity of the friction shifter. Yes, I understand the match doesn't need to be exact, like for indexed shifting; but one still needs to get the match close for best effect. For the rear, that means a 120° swing of the (downtube) friction shift lever should result in a 41mm lateral displacement of the guide pulley on the rear derailleur (41mm is about the width of a 11-speed cassette). For the front, the same 120° swing of the shift lever should result in about a 16mm lateral displacement of the front derailleur cage, to accommodate a typical triple crank. Why limit the effective swing of the friction shifter to 120°, and not, let's say 150° or even 180°? Read on. I want to put in a plug for optionally setting the travel stop of downtube shifters about 30° from parallel with the downtube. In other words, I'll like the shifter's "home position" to be just slightly raised from being parallel with the downtube. Using this design for the left shifter will enable easy actuation of both levers with just the right hand for right-handed cyclists, and using this design for the right shifter will do the same for left-handed cyclists. To enable such a design means ensuring the shifter pulls enough cable within a narrow angle of travel, so the proposed 120°. Interestingly, I haven't tried this yet, but it appears that getting a second set of downtube stop washer <https://www.rivbike.com/collections/shifting/products/silver-shifter-downtube-stop-washer-pair> from Rivbike and using the "opposite" one will allow this 30° offset, so we may not even need any extra SKUs. -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/3708251b-2933-449c-853c-ac7eef2c84f0n%40googlegroups.com.
