Rings on DA 7410 crank
#1
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Joined: Aug 2008
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From: Tucson, Arizona
Bikes: '02 Lemond Buenos Aires, '98 Fuji Touring w/ Shimano Nexus premium, '06 Jamis Nova 853 cross frame set up as commuter, '03 Fuji Roubaix Pro 853 back up training bike
Rings on DA 7410 crank
I picked up a 7410 crank set at a swap meet. I'm not sure if they have the original rings. The big ring is labeled "Shimano SG" and "B-53", all marked on the outer side of the ring and with a grove running around the circumference of the ring beneath the teeth. The inner ring is mounted with no markings on the outer side. On the inner side it is marked "Shimano SG", "TL", "B-39", and a "V" mark positioned right at the crank arm (3rd pic). The inner ring has a "shelf" on both sides running around the perimeter of the ring below the teeth (2nd pic). As mounted, the shelf on the on the inside is about 1/2 mm higher than the shelf on the outside. Is this the correct orientation? Are these original DA 7410 rings? IMO, the condition of these rings is excellent, but I'd appreciate a second opinion. Thanks.
Edit-After removing the rings, I see the ring nut groove on the inside of the bolt holes of the small ring, so it was correct.
Edit-After removing the rings, I see the ring nut groove on the inside of the bolt holes of the small ring, so it was correct.
Last edited by vredstein; 04-16-14 at 10:14 PM.
#2
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From: Above ground, Walnut Creek, Ca
Bikes: 8 ss bikes, 1 5-speed touring bike
they don't look too bad, but IME, an opinion from looking at a pic is worthless. for me, either the chain skips or it doesn't. if it does, i buy a new chain and cogs, and if it STILL skips, i buy a new chainring. other's will have different opinions and no doubt you'll hear them.
#3
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From: Melbourne, Oz
Bikes: https://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=152015&p=1404231
Wow, they're pretty damn mint for 7400! Those are totally DA rings; look how smooth all the edges of the chainrings are. Pretty sure those surfaces are rough on a nice shiny tricolour chainring.
I bet the cranks aren't even scuffed, huh? If they are, these rings would have to be replacements.
Bah. Those chainrings are like 1/4 used, max.
I bet the cranks aren't even scuffed, huh? If they are, these rings would have to be replacements.
Bah. Those chainrings are like 1/4 used, max.
#5
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From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
The mounting orientation is correct and the chainrings are "matched". The corresponding "B" on both rings means they are made to work together. And yes, Shimano rings are mounted so the engraving faces outward on the big ring and inward on the smaller one.
#6
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Joined: Aug 2008
Posts: 704
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From: Tucson, Arizona
Bikes: '02 Lemond Buenos Aires, '98 Fuji Touring w/ Shimano Nexus premium, '06 Jamis Nova 853 cross frame set up as commuter, '03 Fuji Roubaix Pro 853 back up training bike
Wow, they're pretty damn mint for 7400! Those are totally DA rings; look how smooth all the edges of the chainrings are. Pretty sure those surfaces are rough on a nice shiny tricolour chainring.
I bet the cranks aren't even scuffed, huh? If they are, these rings would have to be replacements.
Bah. Those chainrings are like 1/4 used, max.
I bet the cranks aren't even scuffed, huh? If they are, these rings would have to be replacements.
Bah. Those chainrings are like 1/4 used, max.
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Chris_W
Long Distance Competition/Ultracycling, Randonneuring and Endurance Cycling
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04-23-12 09:32 PM





