here's another thread discussing the T.A. drop pin and a couple good pics. I'd guess the spacer is used to lengthen the set-up if there's a larger gap involved, between chainring and crankarm. Having the screw head on the inside is apparently correct but seems undesirable - why didn't they tap the hole so all the working parts could be outboard of the chainring (I guess you'd have to install the drop-pin before installing the chainring that way, so less convenient perhaps). The pics at this link show a 5arm spider but the 5th arm isn't in line with the crank (not hidden). Dave H pointed out the pin is intended for the 5th arm, when hidden I presume. So maybe not needed on this version . . . or do other set-ups still jam to some degree and this could help anyway? https://www.cyclechat.net/threads/ta-chainrings-what%E2%80%99s-this-spacer-for.277396/
On Friday, December 17, 2021 at 11:22:26 AM UTC-8 Joe Bernard wrote: > I just don't understand that solution. All the chain-drop-stoppers I've > seen are a small grub screw that threads into the chainring, there's no > screw/spacer on the backside of the ring. > > > > On Friday, December 17, 2021 at 8:56:21 AM UTC-8 iamkeith wrote: > >> >> Here's an image. One thing to be aware of, assuming your screw head is >> as thick as this: In some gear combinations, when my chain is on the ring >> adjacent to the big/outer ring with the pin, I get a "ticking" as the screw >> head rotates around and hits the chain. Took me forever to figure it out, >> after which I just didn't worry about it. >> On Friday, December 17, 2021 at 2:48:19 AM UTC-7 David Hallerman wrote: >> >>> Yes, I’ve installed many TA chainrings, and that screw/nut/spacer is to >>> be used when the crank is a 5-arm spider. The s/n/s goes on the out-facing >>> side of the big ring to prevent chain drop jamming. >>> >>> With a 4-arm crank, no need for s/n/s. >>> >>> On Fri, Dec 17, 2021 at 12:05 AM Jim S. <jjsi...@gmail.com> wrote: >>> >>>> Hi, I'm installing a T.A. chainring, and it comes with a small screw, >>>> nut, and spacer. I'm perplexed. Does anyone know what these are for? >>>> >>>> -- >>>> 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 view this discussion on the web visit >>>> https://groups.google.com/d/msgid/rbw-owners-bunch/9f2b6f7b-ed5b-4bf0-9564-7000e9ad97c3n%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/rbw-owners-bunch/9f2b6f7b-ed5b-4bf0-9564-7000e9ad97c3n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- 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/79f9d518-47c3-41b6-974a-d4b4fc0a6b40n%40googlegroups.com.
