Hi Bill, Yes, I failed to provide more information; IG-51 chain width - 7.27mm CX70 derailleur width - 9.38 mm (inner width of the upper part of the derailleur where the rubbing occurs)
Front 40 ring Rear cog 11 - rubbing 12 - rubbing 14 - rubbing 16 - rubbing 18 - ok 21 - ok 26 - ok 32 - ok Front 26 ring Rear cog 11 - ok 12 - ok 14 - ok 16 - ok 18 - rubbing 21 - rubbing 26 - rubbing 32 - rubbing *Bill said* *- Which chainring are you on, the 40 or the 26? - *Rubbing happens on both rings (see above) *- Which cog are you in? - Chain rubbing happens on either 4 lower cogs or 4 higher cogs depending on the front ring.* *- Which side of the cage is the derailer rubbing on? - *Rubbing happens on the inside part of the CX70 derailleur (upper part) *- Can you see the chain rubbing on the front der? - *Yes, I measured that part and the width is quite narrow at 9.38mm *- When you turn the appropriate limit screw, can you see the front derailer moving in response to your action? - *Yes Thanks Bill for providing detailed measurements of your existing setup. It looks like I need to buy another derailleur dedicated for 2x8 gearing system. On Fri, Dec 2, 2016 at 2:39 AM, Bill Lindsay <tapebu...@gmail.com> wrote: > I think there is more information that hasn't been shared yet. There is > no good reason in my mind that a CX70 front derailer can't work with a 2x8 > drivetrain. I just went out to the garage and measured a few things. > > I have a 2x10 drivetrain with a CX70 front derailer on it. The inner > width of the CX70 cage is 12.0mm. The outer width of my 10 speed SRAM > chain is 6.2mm. There's plenty of room. I measured the maximum width of a > SRAM PG870 chain on another bike and it is 7.0mm. There still should be > plenty of room to fit a 7.0mm chain through a 12.0mm wide front derailer > without rubbing. > > It would be easy to diagnose if I was looking at it. At any rate, when ed > says: "The chain keeps rubbing the side of the derailleur (CX70) even > after making adjustment to the limit screws." Which chainring are you on, > the 40 or the 26? Which cog are you in? Which side of the cage is the > derailer rubbing on? Can you see the chain rubbing on the front der? When > you turn the appropriate limit screw, can you see the front derailer moving > in response to your action? > > Bill Lindsay > El Cerrito, CA > > > On Thursday, December 1, 2016 at 10:16:29 AM UTC-8, Philip Kim wrote: >> >> I would get a 8 speed sora triple front derailleur. works great. i think >> i have one if you want to just pay for shipping or something. >> >> On Thursday, December 1, 2016 at 7:53:14 AM UTC-5, ed wrote: >>> >>> Hi Belopsky, >>> This morning I realigned the derailleur and it improved just a bit but >>> there is still rubbing. >>> Thanks for the advise :-) >>> >>> On Thu, Dec 1, 2016 at 8:36 AM, Belopsky <belopol...@gmail.com> wrote: >>> >>>> Are you sure the derailler is paraller w the chain? >>>> >>>> >>>> On Wednesday, November 30, 2016 at 7:27:26 PM UTC-5, ed wrote: >>>>> >>>>> I would like to seek your advise to help me build my 55 Cheviot. >>>>> Bought it from Rivendell when I visited them last September 16, 2016. >>>>> The headset, fork, and bottom bracket were pre-installed by Riv. >>>>> >>>>> This is my first full bike build so pardon my ignorance if I have >>>>> chosen the wrong set of components to make this work. >>>>> Currently I am having trouble getting my front derailleur to work >>>>> quietly. >>>>> The chain keeps rubbing the side of the derailleur (CX70) even after >>>>> making adjustment to the limit screws. >>>>> >>>>> These are the gear components installed: >>>>> >>>>> Shifters - IRD Silver SOS power ratchet Thumb shifters >>>>> Front derailleur - Shimano CX70 >>>>> Crank - Sugino XD2 wide/double crank 40t x 26t >>>>> Cassette - SRAM 8 speed 11-32 >>>>> Rear derailleur - Shimano Altus (RD-M310) >>>>> Chain - Shimano 8 speed chain IG-51 (116 links then added 2 more links >>>>> because of the longer chain stay) >>>>> >>>>> Anyone care to comment/suggest on what I could have done wrong before >>>>> I give up and just bring my bike to our LBS. >>>>> >>>>> Ed Fausto >>>>> >>>>> -- >>>> 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-bun...@googlegroups.com. >>>> To post to this group, send email to rbw-owne...@googlegroups.com. >>>> Visit this group at https://groups.google.com/group/rbw-owners-bunch. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- > 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. > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. 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