‘76 Dur-ace chainring
09-26-22, 02:35 PM
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‘76 Dur-ace chainring
At 73, small rises are now hills, looking to change my chainring from 46-41 to 46-?? and the cogs are 14,17,22,27,34….will I need to modify my chain length?
Thanks
Halfmile
Thanks
Halfmile
09-26-22, 03:06 PM
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Hard to say. Chain length is a function of gearing, derailleur capacity, and chainstay length. If your derailleur can wrap the current length with a smaller inner ring, no worries (check on small-small combination). If it can't fully wrap the chain on small-small, take a link or two out, check small-small again for wrap, if good, check large-large to be sure that you're not running the chain too short. If it is too short on large-large after cutting a link, you'll need a rear derailleur with more wrap capacity.
09-26-22, 03:07 PM
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46-34 will be the chain length primary control
I saw long ago 40t Dura Ace. Not sure on smaller
I saw long ago 40t Dura Ace. Not sure on smaller
09-26-22, 04:06 PM
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If your BCD is 130mm, 39T chainrings are available.
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09-26-22, 04:21 PM
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I’d run a different crank with a smaller bcd, so that you can run a 50/34 or a 46/30
09-26-22, 04:59 PM
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I put an early DA crank on my PX10 and later put a 39 and a 45 on it to replace the stock rings but I'd want a triple these days.
