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I would expect the crank spider not to sacrifice much stiffness in expanding from 110 to 130, but the chainrings seem flimsy in comparison.

Do I buy extra stiffness by using a standard chainset instead of a compact?

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I'm slightly confused by your question. You mean for the same size chain rings, like 52-tooth or 39-tooth? Or do you mean a 34-tooth chain ring on a 110 BCD crank vs. a 39-tooth ring on a 130 BCD crank but with corresponding differences in the rear cogs so that the overall gear ratio is held constant? What is the comparison you're trying to make? (BTW, for the same power input and cadence at the crank, force on the chain ring is inversely proportional to the number of teeth on the chain ring, so a 34-tooth chain ring carries 39/34 = 1.15 ==> 15% more force than a 39-tooth ring.) – R. Chung Jan 23 '14 at 18:10
I mean for the same size chain ring, so for example a 53/39 chainset in both 110 and 130 BCD: is one stiffer than the other to any noticeable degree? – Will Vousden Jan 23 '14 at 23:06
I think this would depend a lot on the particular quality of the chainrings. – Batman Jan 24 '14 at 0:00
I doubt that there's a substantial difference, one way or the other. Depends more on the quality of the components than the BCD. – Daniel R Hicks Jan 24 '14 at 0:58

There's little difference noticeable but the chainrings will make a big difference as some cheap ones will flex a surprising amount

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