Chain Rub with Dura Ace Compact Crankset

Discussion in 'Cycling Equipment' started by oldultrarunner, Nov 4, 2011.

  1. oldultrarunner

    oldultrarunner New Member

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    I recently got my new Seven custom Ti/carbon road bike and went with Dura Ace compact crankset. I had the bike shop build the bike. I have a Trek 5500 carbon that I've had for about 8 years with DA triple (9 speed) and I've never had any problems with the shifting or chain/drivetrain noise.

    I wish I could say the new DA 10 speed crankset I bought for the new Seven was better but I am not happy with it at all. The drivetrain is so much more noisy than the 9 speed triple. Several problems I've had with the drivetrain that have given my angst. The drivetrain is very quiet when I'm on the big chain ring and any of the rear cogs (I have the 12-28). But as soon as I downshift to the compact crank, I get loud chain noise on the middle cogs. Also, I get severe chain rub when I'm the compact crank (inner) and the 12 rear cog. The chain rubs against the large chain ring. I had the bike shop look at it and they said it's "probably because of a short chain stay on the custom frame".

    I'm thinking it could also be a chainline problem causing this. Anyone have any thoughts? At this point, I'm about ready to take off the DA groupo, sell it on ebay or craigslist and buy either the SRAM red or go Campy 11 speed.

    Thanks
    Len
     
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  2. alienator

    alienator Well-Known Member

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    You may need to find a different LBS. There is nothing wrong with the Dura Ace group set. It sounds as if you just need someone to adjust the derailleurs and cable tensions properly. Short chain stays can be a bit of an issue, but nothing that can't be massaged.
     
  3. jpr95

    jpr95 Active Member

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    Also, you shouldn't be using your little/little or big/big combos--those are always hard on chains. It's also quite possible that the chain line is wrong--the rear wheel may not be correctly dished, or the front chainrings may not be properly spaced for that bottom bracket/crankset. It may also be that one or both derailleurs are not properly adjusted.

    I don't like hearing drive trains on bikes. All I can hear on my bike are the shifts and the tires on the road. If I can hear it, it gets cleaned and adjusted after that ride.
     
  4. An old Guy

    An old Guy Member

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    Considering that the cassette is a fixed distance from the dropout, there is no rear adjustment you can do except move the drop out.

    Considering that the crankset indexes off the bottom bracket, there is no front adjustment you can do except change the length of the shaft.

    Now you are stuck with the chain line.

    You can adjust the derailleurs so that the chain does not rub against them.

    That is about it.

    Short chain stays and 16 too differences on the front will cause the chain to rub against the large chain ring in the small/big.

    Short chain stays may cause rubbing in either the large chain ring or the small chain ring.Your choice.

    ----

    I think you may have made a poor choice of components. They may never work well on the frame you have.
     
  5. vspa

    vspa Active Member

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    like you were told on this thread: that gear combination is simply prohibited, on any setup you might have,
     
  6. oldbobcat

    oldbobcat Well-Known Member

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    Such is the nature of the beast--short chainstays that give you steep angles when cross-chaining, and a big ring that's 47 percent bigger than the small one. The front derailleur has nothing to do with it because it's the chainring that's getting rubbed, not the derailleur cage. And the brand of drivetrain has nothing to do with it because cassette width and chainring spacing are pretty much identical across brands.

    The DA (7800) standard double on my Giant does it, too. Small-small is just my sacrificial combination. Actually, I don't use the two smallest cogs when I'm using the small ring because of chain slap, anyway.

    If you're using threaded bottom bracket bearings, you could try 1-2 mm of shims behind the drive-side cup, but I'm not going to guarantee that it won't screw up your chain line from the big ring to the other end of the cassette.

    I understand your disappointment, coming from a triple where the entire cassette is accessible from the middle ring, but you don't have that any more. Maybe you should be looking at triples again.
     
  7. Peter@vecchios

    [email protected] New Member

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    COMMON for the chain to tickle the big ring when on the smaller cogs. 10s gotta go somewhere(outboard) and lots of pins and doo-dads on the big ring to hep the chain get up there under load. As for the mid gear noise, newer shimano hidden der housing shifters HAVE to have very smooth movement of the inner wire inside the housing. Get 5mm housing and route the der housing behind the handlebars, not in front.

    BUT if ya don't like it, don't get sram, if ya think shimano is finicky....Chorus is very nice but also relies on smooth inner wire movement.
     
  8. alfeng

    alfeng Well-Known Member

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    As vspa mentioned, cross-chaining should be considered as verböten if you're concerned about a quiet drivetrain.
     
  9. alfeng

    alfeng Well-Known Member

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    FWIW. While you may be ultimately happier with a Campagnolo group of any ilk, your problem can be resolved with a simple understanding of arithmetic and/or geometry ...

    If you don't need a 34t inner chainring then I reckon that your problem will be eliminated if you were to replace it with a 36t inner chainring ...

    • that is, the 36t inner chainring should, but may not, resolve the chain rubbing against the ramps-and-pins of the outer chainring

    If you need the 34t inner chainring to achieve a suitably low gear ratio, then get the 36t chainring + choose a cassette whose largest cog is about 2t more than your current cassette's largest cog (i.e., 30t ... I'm pretty sure that MICHE makes individual cogs ... don't worry if it is a 9-speed 30t cog ... just restack your current cassette & eliminate one of the intermediate cogs ... BUT, you may want to try a few rides with the 36t inner & 28t largest cog before worrying about either buying a new cassette or restacking your current cassette).

    OR, choose a "standard" crankset with a 39t inner chainring + a "pie-plate" cassette whose largest cog is 32t :

    [​IMG]

    BTW. You want to ensure that your bike has the latest, asymmetrical iteration of the 10-speed SHIMANO chain & that it is not installed inside-out ... accept NO SUBSTITUTES,
     
  10. danfoz

    danfoz Well-Known Member

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    You will get more chain rub against the large chainring from a 34 than a 39 with ANY brand, not just Shimano. When I got back into cycling a few years ago the bike I purchased had a compact by FSA. Same wicked chainrub on the 12, 13, and even some on the 14 while on the 34T. I thought it was just a funky crankset, then went to a Shimano compact, same thing. Finally switched over to a regular crank size crankset and the rubbing problem was resolved.

    More chain rub will occur along the big ring as the distance between top chainline and bottom chainline decreases. No need to get rid of that groupset, maybe just swap the crankset if you absolutely want to run small/small combos. Unless you plan on keeping the same chain for several years, the wear caused by running small chainring against the 2nd smallest rear cog will be a non-issue.
     
  11. oldultrarunner

    oldultrarunner New Member

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    Chainline is fine, I measured it and it's ok.
     
  12. oldultrarunner

    oldultrarunner New Member

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    You can't do that with Dura Ace 10 speed. It's a compact crank and they don't even sell a crankset with a 50/36. And as for a rear cassette change, the biggest cassette you can get in DA is a 12-28 (or 11-28). You can't get anything higher than that. This is top of line drivetrain here, not Sugino where you can swap out chainrings and make adjustments to get it to work.
     
  13. oldultrarunner

    oldultrarunner New Member

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    I live in Colorado and uh, we have hills and mountains here, so going to a 53/29 is really out of the question for a 60+ aged rider who rides 300-400 miles a week and 70% of it in the mountains. I went with the DA compact crankset only because Shimano no longer sells a triple crankset in Dura Ace. They do in Ultegra but I didn't want Ultegra. I have a 2002 Trek 5500 that I have probably in excess of 70K miles on the drivetrain. Those components are the original components other than a chain and cassette changed routinely when it gets worn. So I believe DA has the best reliability for the long haul in the amount of riding I do. So I went with the compact crankset knowing I'd be sacrificing some low gearing on climbing compared with the 9 speed triple (53-39-30). But I've never had any chain rub on that DA triple so I'm kind of disappointed in shelling out $2300 for this new DA compact crankset. It's not nearly as good as the old DA 7700 9 speed triple. Much more noisy and shift is much less precise and quick than the 7700. Wish I could find a new DA 7700 for the Seven.
     
  14. dhk2

    dhk2 Active Member

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    Yeah, I'm very happy with my 7700 triple setup. With 53/39/30 and a 12-27, I've got the gearing I like. It's never required any maintenance in 30K miles and 7 years other than one cable change. But not sure it's any more durable than Ultegra; I had that on my previous bike and didn't have any trouble with that either. Do you have any evidence to think that Ultegra won't last as long as DA?

    I do get light chain rub when in the middle ring and on the outer two cogs. As Peter said, it's just the chain tickling the big ring. It doesn't bother me, since I rarely use that combo. Front shifting is easy on the triple, so no need to cross-chain. Going to a 52 big ring would of course lessen the problem.....if you could get a 50 or 48 that might fix it.

    You don't ask for advice, but you could sell the DA compact and get an Ultegra triple. Why have a new bike if it's not set up the way you like it?
     
  15. alienator

    alienator Well-Known Member

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    First, Sugino makes excellent stuff and have for a long time, and with top of the line drivetrains you can make adjustments to get things to work just fine.....hell, more than fine. Dura Ace is no exception. There may be some other issue you haven't found.

    I agree with dhk2: Ultregra cranks and chainrings will be just as good as Dura Ace. The only real difference between the two groups is weight. The Ultregra crankset has actually been tested and shown to be stiffer than the Dura Ace version. That might be important if your a stiffness junkie. I also agree that if you want a triple, get what you need for a triple set up. There certainly is no reason, especially in the mountains, to have less than what you need or are comfortable using.
     
  16. alfeng

    alfeng Well-Known Member

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    Well, pardon me!?!

    While I presume you are referring to my Campagnolo Record crankset as a Sugino crankset, there is no reason that you cannot replace the chainrings on your "top of the line" Shimano crankset with either different Shimano Dura Ace chainrings or with chainrings made by someone else.

    • I believe that Sugino is still the preferred choice of non-sponsored Track riders
    • as alienator has already noted, Sugino makes excellent cranksets
    LEKTION EINS. The inner chainring on-or-for a Double crankset is not ramped. So, as far as replacing the inner chainring, the only thing(s) a person truly needs to be concerned with is the BCD + the cosmetics, with the latter being a trivial matter.

    Rather than spend several hundred dollars to buy a hypothetical (regardless of whether or not it is available) 50/36 DA crankset, you would simply buy a 36t 110BCD chainring and install it in place of the existing 34t 110BCD chainring.

    OR, were you planning to replace the entire crankset when you wore out the crankset's 34t (or, 50t) chainring?!?

    LEKTION ZWEI. While I 'love' Shimano components and I have the highest regards for their engineers (okay, their mechanical shifters continue to leave something to be desired, IMO, but the deficiency has resulted in 20+ years of R&D which has benefitted the cycling world through the ramping-and/or-pinning found in their-and-other drivetrains), but their marketing department is suspect, IMO.

    • A dozen years ago, I was told that you couldn't mix any Shimano components which were not labeled with the same Group name. Well, through necessity, I figured it was worth experimenting with my Ultegra 6500 shifters + an XTR rear derailleur + an XTR cassette -- at the time, it was an unheard of combination ... not so much so, now.

    Even YOU can substitute an 11-32, 10-speed Shimano XTR cassette for your 12-28 cassette. While dated-by-comparison, here's a 9-speed 12-34 XTR cassette + DA rear derailleur (the 11t upper pulley wheel was replaced with a 10t pulley wheel):

    [​IMG]

    It's true that the above combination isn't on a fancy-schmancy "new Seven custom Ti/carbon road bike" ... but, I have found that frames with an off-the-peg geometry suit me:

    [​IMG]

    I suppose that my Colnago C40 frameset didn't cost as much as your "custom" Seven frameset may have cost ... or, maybe it did. Regardless, that's a 2001 frameset whose 2011 equivalent would probably cost more (but, which I probably wouldn't buy, now).
    I've changed the components on my C40 over the years ... only the Campagnolo Skeleton brake calipers & Shimano DA rear derailleur were chosen for cosmetic reasons over the components they replaced.

    LEKTION DREI. Now, if you were to do some simple arithmetic, you would realize that a 34t chainring + 28t largest cog is the SAME AS a 39t chainring + 32.11t cog (okay, there's NO 32.11t cog, but a 32t is certain numerically close).

    Further, a 36t chainring + a 29.647t cog (oops, there's another impossible cog!) is equal to a 34t chainring + 28t cog, and vice-versa.

    FYI. I generally ride on mountain roads, with my preference being the roadway which was formerly known as "South 14" -- the altitude ranges from 6500 to 9000 feet. The popular roadway to "The Crest" reaches 11,000+ feet & I'll admit that is too much climbing for me.

    Here is one of my in-city ("Flatlander") bikes as it was originally set up:

    [​IMG]

    Since taking the picture, I made cosmetic changes which involved replacing the seatpost with a Campagnolo seatpost AND the pictured Shimano DA 7700 crankset & 50t FSA chainring with a 5-arm Campagnolo Chorus crankset + 50t Gebhardt chainring.

    LEKTION VIER. I 'love' Shimano components. I have both Dura Ace & Ultegra components, and while there is weight difference, as far as I am concerned the difference is mostly cosmetics & cost ...

    Regardless, a knowledgeable weight-weenie would opt for Campagnolo components over Shimano, so to argue that Dura Ace components were chosen because they weigh less is a hollow rationale for the choice of DA over Ultegra.

    LEKTION FÃœNF. If you are patient, you can probably buy a NOS Shimano 7703 crankset on eBay. If you are not patient, then you can probably buy a NOS Shimano 7700 crankset and then install a TRIPLIZER inner chainring (available at Harris Cyclery, etc.) + any "standard" (74BCD) Granny chainring rather than dealing with the proprietary 7703 middle-and-granny chainrings.

    • I know someone in Santa Fe who set up a Triplizer with a 22t Granny + Shimano 7703 shifters.

    LEKTION SECHS. I found that a 112.5mm XTR BB is suitable for any Octalink Road Double + any Octalink Road Triple crankset -- specifically, I used the 112.5mm XTR BB with an Ultegra Triple crankset.

    • Depending on how the stays are shaped, the shorter, 112.5mm spindle may not work with an aluminum frame.

    While the chainline with a 112.5mm XTR BB isn't as good as with a 109.5mm Octalink BB, it is certainly better than with a 118mm Octalink BB.

    While the XTR BB requires a 2.5mm BB spacer (or, equivalent), I found that the XTR spindle will fit in the non-cartridge DA Octalink BB cups.

    ---​

    YOU have many options ...

    Some of your options will cost more money than others ...

    OR, you can ignore all the suggestions given to you by various Forum members & you can continue to complain about how your LBS set up your "custom" bike (or, did you assemble it?) OR you can lament your inability to cross chain the small-small combinations without the chain grinding against the outer chainring.
     
    steve likes this.
  17. Eichers

    Eichers New Member

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    Quote:
    Originally Posted by oldultrarunner .

    I live in Colorado and uh, we have hills and mountains here, so going to a 53/29 is really out of the question for a 60+ aged rider who rides 300-400 miles a week and 70% of it in the mountains. I went with the DA compact crankset only because Shimano no longer sells a triple crankset in Dura Ace. They do in Ultegra but I didn't want Ultegra. I have a 2002 Trek 5500 that I have probably in excess of 70K miles on the drivetrain. Those components are the original components other than a chain and cassette changed routinely when it gets worn. So I believe DA has the best reliability for the long haul in the amount of riding I do. So I went with the compact crankset knowing I'd be sacrificing some low gearing on climbing compared with the 9 speed triple (53-39-30). But I've never had any chain rub on that DA triple so I'm kind of disappointed in shelling out $2300 for this new DA compact crankset. It's not nearly as good as the old DA 7700 9 speed triple. Much more noisy and shift is much less precise and quick than the 7700. Wish I could find a new DA 7700 for the Seven.


    Hi oldultrarunner, one fellow on the forum (I can't remember his name or the exact post), who uses a DA 7900 SS RD and DA 7900 50/34 Compact Crankset, posted that he was able to run an 11-32 MTB cassette (I can't remember if it was a Shimano or Sram 10spd cassette) without any issues. He did not mention any scrapping issues, only that it worked successfully, actually I think he mentioned the word "perfectly". An 11-32T cassette and 50/34T compact crankset should allow you to get up any hills :)

    Here's another thread you may like to read ... http://www.cyclingforums.com/t/477148/an-alternative-to-using-a-compact-crank-set

    It is probably unlikely, at least at this time, that you can get other than a 34T chain ring for your DA 7900 Compact Crank.
    But perhaps alfeng knows where you can 36T DA 7900 110 BCD chain rings from :)
     
  18. alfeng

    alfeng Well-Known Member

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    I guess the combination of my initial typo(s) & an apparent lack of emphasis means that repetition is in order -- to quote myself:

    • The inner chainring on-or-for a Double crankset is not ramped. So, as far as replacing the inner chainring, the only thing(s) a person truly needs to be concerned with is the BCD + the cosmetics, with the latter being a trivial matter.

    Consequently, almost any 3/32" 110BCD chainring (except Campagnolo's!) will fit on the Compact 7900 crankset ...

    Now, DA & Ultegra chainrings were-and-presumably-still-are nickel plated to help them last longer ...

    • I doubt one DA-or-Ultegra ring will last longer than three "regular" alloy chainrings (e.g., a 105 chainring)
    • to ensure longevity on my "winter" bike's inner chainring, I replaced the original 39t Dura Ace chainring with a 39t steel inner chainring -- the 39t steel chainring bears a small weight penalty for easily more than 3x the wear of one of Shimano's nickel plated chainrings ...
    • undoubtedly, I have one of the few -- if not the only -- Dura Ace crankset which has a steel chainring.

    I believe the inner chainring on a 7900 crankset is black, or nearly so ...

    Paint it, if necessary, with some flat black paint.

    If the acquired chainring isn't black, then paint it if that is the desired matching color with the original chainring.

    FSA & Token chainrings are generally a glossy black, BTW.
     
  19. Eichers

    Eichers New Member

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    Hi alfeng, no worries, please post a url (link) of where you can get a compatible 36T 7900 inner chain ring. That would be terrific ... thanks
     
  20. oldbobcat

    oldbobcat Well-Known Member

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    You got me looking and I could not find a 7950 36t ring anywhere, even in Shimano.com. For 130 mm you have several options. but with 110 mm 50-34t is all you get.

    You can order a 50-36t Shimano-compatible set from Praxis Works, though. http://shop.praxis-works.com/Compact-Road_c4.htm. 36t ring may have been available for 7800-series compacts.

    My Felt F5 had 50-36t FSA Gossamer rings. I don't remember if the chain rubbed when I ran 36/11, but I do remember the chain bouncing around so much that I doubted ever getting a clean shift out of that combination..
     
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