John: How about using your 9 speed cassette as an 8 speed by adjusting out lowest or highest gear with a limit screw, assuming you can so without one of those gears?
Sent from Yahoo Mail on Android On Tue, Nov 29, 2022 at 2:00 PM, Ted Durant<[email protected]> wrote: On Tuesday, November 29, 2022 at 2:36:34 PM UTC-6 John Hawrylak wrote: Did you measure the RD ratio's or are they a published value somewhere?? I have seen some published, but my memory is that I measured them from the total distance between cogs and the total amount of cable pulled. Do you happen to know the ratio for a Shimano Deore M-591-SGS?? I have this with a Shimano 9sp road cassette (4.34mm cog spacing). Classic Shimano 6-7-8-9 (and 10 Road) derailers are 1.72. The RD ratio would have to greater than 1.39 for the SunTour barcon 25mm travel to shift the 8 cog spacings on the 9 speed cassette (8 * 4.34)/25 = 1.39 Well, I have Shimano 9 at 4.35, not 4.34, but otherwise I concur :-) My spreadsheet says you need 20.2mm of cable pull to shift a Shimano 9-sp derailer across a Shimano 9-sp cog set, so BarCons should have plenty of capacity. Just don't try to put a SRAM road derailer on that setup - you'll be a couple mm short. Newer derailers are using lower actuation ratios so that more cable pull is required for each shift, so that there is more room for error. So, any derailer that pre-dates the 11-speed era, other than SRAM "Exact Actuation" will probably be a good match with BarCons. Ted DurantMilwaukee, WI USA -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/9a74b190-2375-434f-8fb6-cc30c9b27cb8n%40googlegroups.com. -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/1160249207.5083218.1669756393759%40mail.yahoo.com.
