If the derailleur works with the TA arms, it should shift to the new bigger ring. The problem with new wide cage deraillieurs and TA cyclotouriste arms is that the deraillieur can rub on the arm by the time it moves enough to shift the chain to the big ring.
The downside with too big a jump between the middle and big ring is that the middle ring may "hide" in the shadow of the big ring, and the chain may want to shift from the small ring directly to the big. The shaped cage of a modern derailer can mitigate the problem but then it might hit the crank arm---. Can you say Catch 22?
I've used a first generation Shimano Deore with a "racing triple" TA crank (52x42x30), and it seemed to shift fine.
Tom Adams, Shrewsbury NJ.
>From: "Tom Sanders"
>Reply-To: Tom Sanders
>To:
>Subject: [CR]Advice oh half step gearing sought, or once again compulsionrears it's ugly head!
>Date: Mon, 22 Sep 2003 15:25:21 -0400
>
>Well I'm off again on another project. I just bought a bike with half step gearing and I can't say that I like the idea of it very much. I have a bike with a Specialities T.A., cyclotouriste(sp) crankset,170mm arms, half step/granny rings, 44/40/26. My question is can I just replace the outer chainring with, say, a 52t and be back to normal shifting? I have heard that the front derailleur is different on a bike with half step gearing (They lost me there!)...hopefully I'll be all right there?
>Any advice will be received with much gratitude and points will be built up in Heaven for those doing such good deeds, I'm sure.
>Thanks,
>Tom Sanders
>Lansing, Mi
>
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