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Dura-Ace 7900 crankset upgrade

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Dura-Ace 7900 crankset upgrade

Old 05-27-13, 01:57 PM
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Dura-Ace 7900 crankset upgrade

I am interest in possibly upgrading my compact (50/34 or maybe it's a 36) and was told I would need to buy an entire new crankset to go to a 53/39 combination. Is this true? Or can one buy the 79xx series chainrings separately and save a few hundred $$$???
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Old 05-27-13, 04:32 PM
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Your 50/34 crankset is built on a 110 BCD platform, and most road cranksets using 38 or 39 inners (or larger) are built on a 130 platform.

However, I used to see road chainrings for 110 BCD cranks for mtb or hybrid conversions, so if you don't mind some declassee generic rings, you might be able to make the switch w/o buying a crankset.

OTOH, you can often find deals on last year's cranksets for less than the cost of a pair of rings, so look around before spending dough either way.
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Old 05-27-13, 04:54 PM
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If you keep your eyes peeled you can probably find somebody with a standard DA crank who wants to trade. You're close enough to mountains that I'd think you'd enjoy a compact.

You could probably go to a midcompact set of chainrings on your same crank too - 52/36 fit on a 110 BCD crank.
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Old 05-27-13, 04:59 PM
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So you have a compact but you want 53/39 rings? You can certainly buy new rings. They might not be Dura Ace but I'm sure 53/39 rings for a 110 BCD crank. But...

Compact cranks are in demand, and lot of people (myself included) would be happy to trade their DA 'standard' (53/39) crank for a compact. I would go that route. It won't cost you anything, and will be a win-win for you and for someone looking for the lower gearing of a compact.
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Old 05-27-13, 05:35 PM
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You can get quality rings by other companies. Specialities-TA are used by many in the pro peleton and come in every size. They also come in matched pairs with the pins and rams phased correctly.
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Old 05-28-13, 04:22 AM
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Non-7900 rings might look strange on a 7900 crank.
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Old 05-28-13, 04:20 PM
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Thanks, everyone, for the input. It's a thought merely at this point of an option. The idea is that I would like to be able to motor along at higher speeds on the flats here in CO (we do have some of these in a few places) and eventually I would like to have two road bikes, one with compact gearing and one with standard gearing, so that I can change depending on where I will be riding.
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Old 05-28-13, 08:20 PM
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If you have a 50 up front and an 11 cog in back (or even a 12), that is a big gear, and is more than enough for flats, and most down hills. Perhaps you need to develop more leg speed to get faster. In other words, the gears are not holding you back.
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Old 05-29-13, 07:07 AM
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Hi,

a 53 over a 50 is 6%, its not much, half a gear or less for me.

(52/42 and 14,16,18,20,22,24,28 - 40 to 100 gear inches)

Much easier and more effective to change your rear gearing to suit.

A twelve for me would up gearing by 16%, but I don't need it.

rgds, sreten.
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Old 05-29-13, 06:28 PM
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Again, thanks for the input. I have an 11-28 in the rear and I think I will aim to keep this one. Again, the idea is that maybe a bigger front will strengthen my legs more and if eventually I get a second road bike then it will have a compact, which i would use when I specifically want to do climbing rides. (This is one of many ideas that tempt me, so I am by no means at the point of obtaining, or looking too much yet for the needed parts to make the change.)
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Old 05-29-13, 07:11 PM
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Originally Posted by martytardy
eventually I get a second road bike
Now yer talking!
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