Results 1 to 7 of 7
  1. #1
    mtbr member
    Reputation:
    Join Date
    Mar 2006
    Posts
    61

    10 speed XT M770 3 ring Crankset with 9 speed XT M770 complete drivetrain.

    I am faced with a problem. LBS says that the 10 speed xt M770 crankset will work with my complete 9speed XT M770 drivetrain. I am concerned based on some of the posts that I have read.

    LBS states that the 10 speed and 9 speed XT M770 crankset are exactly the same except the number of teeth on the crankrings. also stated that the FD and shifters will work without problem with the 10 speed crankset.

    Is this true or should I put a stop to it before they install it on my bike on monday.


    Please let me know your thoughts.

  2. #2
    Fat-tired Roadie
    Reputation: AndrwSwitch's Avatar
    Join Date
    Nov 2007
    Posts
    14,274
    Did you read the sticky?

    Front derailleurs are relatively forgiving. I think you're fine. At worst, you may find you need to use a 10-speed chain.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  3. #3
    mtbr member
    Reputation:
    Join Date
    Mar 2006
    Posts
    61
    I did read the sticky lots of helpful info but I did not see exactly whay I was looking for.

    with the 10 speed chain does it have a different length linkage than the 9 speed chain? Why would I need a 10 speed chain when I am still running everything else 9 speed.

    I am thinking about just buying the xt M770 9 speed crankset from Jenson USA and say forget any potential problem. The only current problem is that I will have to wait for my bike for another 4 days.

    Thanks,

  4. #4
    Fat-tired Roadie
    Reputation: AndrwSwitch's Avatar
    Join Date
    Nov 2007
    Posts
    14,274
    Supposedly, slightly narrower spacing. I haven't played with one myself. 10-speed chains are narrower.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  5. #5
    mtbr member
    Reputation:
    Join Date
    Mar 2011
    Posts
    964
    I used a 10 speed 105 50/39/29 triple with a 9 speed XT/SLX rest mix for a long time with no issues. The 10 speed and 9 speed chains have the same internal width but the 10 speed has narrower plates therefore over all width is different. I have read that some people had issues with chainsuck shifting under load with the 10 speed crank and 9 speed chain but I did not have that issue - I also tried a 10 speed chain with the 9 speed cassette and that worked fine too. The spacing of the chainrings is very slightly different I think between 9 and 10 speed but not enough to make a difference.
    BTW This was all non dynasys - I haven't used that yet

  6. #6
    mtbr member
    Reputation:
    Join Date
    Mar 2006
    Posts
    61
    From everthing that I have been reading through the forum, the biggest problems that I am concerned about is the spacing of the crank rings on the xt 10 speed crankset. The entire xt group is new. Happy birthday to me from my loved ones.

    I figure if i am paying the same price for a new crankset and the rest of my components are 9 speed I might just go out and get the xt m770 9 speed crankset. I just want to make sure that it works like it supposed to.

  7. #7
    mtbr member
    Reputation:
    Join Date
    Mar 2011
    Posts
    964
    Probably not a bad idea if your happy to wait, I ended up with a mix of 9 and 10 spd because after 8 months of 50km a day commuting the stock wheels and 7 spd Acera stuff on my hybrid was toast. I went discount / fleabay shopping and picked the whole lot up - new / near as damit new for under $200. (not including the wheelset)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •