dura ace chainring question



zaku

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Jun 23, 2004
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did the dura ace 7800 ever came with this kind of chainring or this has been swapped? the chain ring prints shimano SGX-53B if this helps.. :confused: :confused:

pic:
dsc01226sn5.jpg
 

alfeng

Well-Known Member
Jul 23, 2005
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zaku said:
did the dura ace 7800 ever came with this kind of chainring or this has been swapped? the chain ring prints shimano SGX-53B if this helps.. :confused: :confused:

pic:
dsc01226sn5.jpg
FWIW. The outer ring appears to belong to an Ultegra 6600 crankset ...

The inner ring seems to be from a triple! A slight amount of unnecessary material, but it means that the ring is marginally (to an insignficant amount, no doubt) stiffer because of its shape.

BUT, does it REALLY matter to you?

IMO, the shape of the web of the Ultegra outer chainrings generally looks better than the shape of the web on DA rings ... and, more so, with regard to the PLATE appearance of the "standard" 7800 outer chainring.

So, the chainrings may indeed have been swapped; but, unless you paid bust-out-retail for the crankset, you should be thankful that the outer chainring isn't the DA outer chainring ...

Beauty is in the eye of the beholder ... and, I would prefer to have those Ultegra rings than the standard DA rings.
 

zaku

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Jun 23, 2004
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thanks for the info!

i also noticed the second ring looks like from a tripe as it has all those curves and indents. but it is actually ok though like this? and since they are ultegra chainrings, if i put a dura ace 10 speed chain will it matter (cassette, and derailleurs will be dura ace 10 speed) ?

ultegra rings actually looks ok to me too but i thought the material are different? or are they the same? just different shaped?
 

alfeng

Well-Known Member
Jul 23, 2005
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zaku said:
i also noticed the second ring looks like from a tripe as it has all those curves and indents. but it is actually ok though like this? and since they are ultegra chainrings, if i put a dura ace 10 speed chain will it matter (cassette, and derailleurs will be dura ace 10 speed) ?

ultegra rings actually looks ok to me too but i thought the material are different? or are they the same? just different shaped?
AFAIK, both DA & Ultegra rings are nickel plated ... with the DA rings usually having a slightly polished appearance & the Ultegra rings being matte.

There may be a difference in the quality of the plating because the non-TT DA rings generally have a distinctive color, at least in the case of the older 7700 rings.

The underlying alloy is the same. Essentially, Ultegra rings are as good as DA rings with regard to material quality ... Ultegra rings are significantly better than 105 rings which are an uncoated & a softer alloy ...

I've seen 9-speed vintage DA rings whose plating has blistered ... I don't know why-or-how that happens. I've never seen the same phenomenon on an Ultegra ring.

Your particular Ultegra ring is a 10-speed ring, so you should be good-to-go with the rest of your drivetrain.

The inner ring (of unknown heritage) is "okay" with the superfluous (for a double) pinning-and-ramping ... it just means the ring is probably a little heavier than a 39t ring that was only intended to be used as part of a double crankset. It may wear more quickly than a DA-or-Ultegra 39t ring because it appears to be simply polished aluminum ... time will tell.
 

zaku

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Jun 23, 2004
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i've heard there was that difference in cold or hot forged? is that a difference too?

the inner ring actually have "shimano" engraved on it so i'd say at least it's a shimano ring. and the color, material looks the same to me as the bigger ring.. but did ultegra ever had triples?? :confused:
 

alfeng

Well-Known Member
Jul 23, 2005
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zaku said:
i've heard there was that difference in cold or hot forged? is that a difference too?

the inner ring actually have "shimano" engraved on it so i'd say at least it's a shimano ring. and the color, material looks the same to me as the bigger ring.. but did ultegra ever had triples?? :confused:
AFAIK, the DA & Ultegra chainrings should be thought of as equivalent, so I wouldn't fret over it. They continue to be the chainrings against which others are compared.

Someone else will have to tell you about the specific fabrication process ...

With regard to the 105-and-lesser rings, they are good-enough. They appear to be stamped out & pressed into shape -- the "ramps" (actually, the bulge) on the back side and the chainring bolt holes are not milled.

Yes, there were-and-are Ultegra triples beginning with the 6503 (9-speed) group, and an Ultegra triple crank & derailleurs (and, shifters!) are currently available.