ISO: 50.4 BCD outer chainring
06-06-23, 10:36 AM
#1
Myrtle Beach Crab
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ISO: 50.4 BCD outer chainring
looking for a chainring in the mid 30's.. i'm running a 44t single right now with a 4 speed 14-22 4 speed rear and my legs doth complain. 3/32
06-06-23, 01:54 PM
#2
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You can buy new TA rings, but it looks like the smallest outer is 40 teeth. Two sources are https://www.veloduo.co.uk/collection...nt=34104480583 for 25 pounds or TA itself - https://specialites-ta.com/pro-5-vis...denture,40-dts, 40 euros.
I bought a TA ring from Veloduo Cycles a few years ago, and the transaction was fast and clean.
I bought a TA ring from Veloduo Cycles a few years ago, and the transaction was fast and clean.
06-06-23, 02:56 PM
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You can buy new TA rings, but it looks like the smallest outer is 40 teeth. Two sources are https://www.veloduo.co.uk/collection...nt=34104480583 for 25 pounds or TA itself - https://specialites-ta.com/pro-5-vis...denture,40-dts, 40 euros.
I bought a TA ring from Veloduo Cycles a few years ago, and the transaction was fast and clean.
I bought a TA ring from Veloduo Cycles a few years ago, and the transaction was fast and clean.
06-06-23, 03:40 PM
#4
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Or you could go triple. 
06-06-23, 03:56 PM
#5
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Even simpler and cheaper - go double. The same sources (and others) sell inner/middle rings in even numbers from 26 to ...um... 52.
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06-06-23, 06:44 PM
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Myrtle Beach Crab
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looks like Bob at freewheel spa has a solution to my old legs.. a custom freewheel to fit my 4 speed spacing and hub.
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06-07-23, 03:29 AM
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Get a crossover-sprocket from a tandem drive (30T pictured, I've seen mention of 34):
Last edited by oneclick; 06-07-23 at 03:33 AM.
06-07-23, 05:57 AM
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Brilliant idea with the tandem chainring suggestion.
Bob’s also a brilliant idea.
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06-10-23, 01:38 PM
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I've seen, but usually unavailable, some adapters to use a 50.4 BCD crank arm with chainrings of a different BCD (larger); no ideal what the lower T limit is on those, however. But I suspect it would look cool (lots of chrome bolts).
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06-14-23, 07:33 PM
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09-07-23, 02:42 PM
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Hi, I'm wondering if you sorted this out because I am in need of a 44 TA outer (50.4) to make a half step double out of. I know yours is a single but I could probably drill it. Thanks.
09-07-23, 04:06 PM
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The Simplex 5-to-3 bolt adaptor gets you to 36, sorry don't have one, the pics I see are associated with large figures in front of dollar signs.
If you are going to spend money you might find a hobbyist who would do this (is a 54 but it'll go down to 28):
09-08-23, 04:58 AM
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And a quick look shows rings down to 34T, I do not know the lower limit: RING
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09-09-23, 11:59 AM
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