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  1. #1
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    30/40T 2X9 direct mount FD on Cannondale Flash 29'er?

    Duplicate thread from drivetrain forum

    Hi, I'm looking for some help from some of the tech guys out there. Here's my situation: I'm looking at a Cannondale carbon flash 29'er "2", which has front derailleur posts integrated into the carbon frame and a direct-mount SLX front derailleur. It comes with a standard 22/32/44 crankset (BB30) and X7 trigger shifters. I currently have an SI Hollowgram crankset set up with a compact 5-arm spider and 30/40T rings from Middleburn. I use this crank/ring setup on my current bike with an SLX clamp-on front derailleur and XT shifters, using the limit screws and cable adjustment set to use the lower 2 shift positions of the XT shifter. I'm really happy with the crankset and ring setup I currently have and would like to use it on the new bike. I would also be considering a set of XO grips to upgrade the X7 triggers.

    So, what do I need to get for a front derailleur? The seat-tube isn't round, so I don't think I can just use a clamp-on without fabbing some special adapter. I'd guess that the SLX that comes with the bike would not work because it is designed for 44T. One thought would be to try an XX FD made for a 39/26 combo since the 40T is so close it seems possible this would work. However, would the XX FD be compatible with the X7 shifter or the XO grip? Sram's website says the shifters are 2X10 only, but is the cable pull truly different than a normal 3X9 front shifter? Another option might be to mod the SLX derailleur by slotting the holes to drop it down for the smaller chainring. A 3rd option would be to go all-out and get an XX derailleur, XX rings, an XX-compatible spider for my crank and an XX front shifter. Lots more $$$ than I'd like to part with. Perhaps a 4th option would be to get an XX front shifter and front derailleur - I'd have to guess this would work, even if not recommended.

    Any other good ideas? I'm open to bending a couple rules here; it doesn't have to be "by the book". It does have to work reliably and fit within a family budget. 2X9 is "must-have" for me on the new bike - I'm unwilling to buy the bike if I can't get 2X9 shoe-horned in somehow. Thanks for any help!

  2. #2
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    Depending on chainline, I'm not sure why the DM SLX wouldn't work as is with your gearing. I've got a DM SLX f. triple derailleur mounted to Shimano's specs for a triple and a 22-32-bash guard crankset, and it shifts fine, even though the derailleur lines up well above the 32 ring in the outer position. I'm using XT triggers.

  3. #3
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    why not get a 42/29 and use the stock front deraillieur?

  4. #4
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    Hey Ted, Randy here. I think you would be ok with the XX front der. as long as you can mount it ok to clear the 40t ring. Shifter compatability shouldn't be an issue.

  5. #5
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    http://www.sram.com/_media/techdocs/...ifications.pdf

    Check out this document. There is a section on direct mount der.'s. You'll have to check the measurements. After looking at the der. it doesn't look like you can move it up or down for different size rings because the der. has round holes. Is the frame mount slotted. If so you may still be ok.

  6. #6
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    Quote Originally Posted by HAL 9000
    why not get a 42/29 and use the stock front deraillieur?
    Because he's running a 29er. 42 is an awfully tall gear with that wheel size.

  7. #7
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    I can get you a Cannondale 42/29 chainring set. PM if you want to make the change.

  8. #8
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    do what i did then...

    cannondale sram XX hollowgram spider



    sram xx 26/39 chainrings from chainreactioncycles.com

    http://www.chainreactioncycles.com/M...?ModelID=42790

    and a sram xx S3 direct mount bottom pull 39t fron derailleur.

  9. #9
    FIRENZE rulez !!
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    SLX has a spacer

    so fitting it on a Flash as triple derailleur

    mounting 2 x 9 set up you have to change derailleur

    XX S3 as told by Hal9000 , i have too, is installed without spacer

    so it is closer to center line , what do you need for a better chainline and better shifting performances

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    Thanks for all the suggestions, guys! I think the 42/29 would be a little taller than I would like. Plus, I would still be concerned that if the derailleur position is set for a 44T ring it would not work well with the 42 unless I could move it down a little bit. I like the sounds of the XX ring/derailleur setup. It's a little spendy, but if XX is as good as everyone says, it would be a nice upgrade. Hal 9000, I think you are running full XX. Does anyone known if it's possible to run the XX derailleur/rings with a normal front shifter (X7, XO or similar)? It seems like the shifter pull in the front may be so close to being the same that it really wouldn't matter.

    -Ted

  11. #11
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    i have these rings

    37 and 25 , XX specific 120 and 80 mm BCD , made in italy

    planned to install on my flash 29er on a lightning crankset
    Attached Thumbnails Attached Thumbnails 30/40T 2X9 direct mount FD on Cannondale Flash 29'er?-hpim0310.jpg  

    30/40T 2X9 direct mount FD on Cannondale Flash 29'er?-user64_pic423_1263380665.jpg  


  12. #12
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    Quote Originally Posted by tjhanes
    Does anyone known if it's possible to run the XX derailleur/rings with a normal front shifter (X7, XO or similar)? It seems like the shifter pull in the front may be so close to being the same that it really wouldn't matter.

    -Ted
    yes front derailleur XX can be commanded from every shifter

  13. #13
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    Quote Originally Posted by tjhanes
    Thanks for all the suggestions, guys! I think the 42/29 would be a little taller than I would like. Plus, I would still be concerned that if the derailleur position is set for a 44T ring it would not work well with the 42 unless I could move it down a little bit.
    -Ted
    no you can put a 42t on and it will shift fine on my scalpel i took the 44t off and put on a 42t didn't touch the front deraillieur and never had an issue.

    middleburn and blackspire make a 40t and a 38t that will fit a 94bcd spider.

    i've been running the 26/39 and 11/36 combo on my 29er and other than our trip out to west texas last month never have had to shift the bike outta the 39 the XX cassette gice you a great spread of gears.

  14. #14
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    They are now making direct mount front derraileurs for specific 2 x 10 chainring sizes. SRAM sizes theirs based on the outer ring size and Shimano sizes their e-type derailleurs based on thel inner ring. For Shimano, you remove the etype mount in order to directly mount to the frame.

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