Results 1 to 6 of 6
  1. #1
    mtbr member
    Reputation: pulser's Avatar
    Join Date
    Dec 2004
    Posts
    1,571

    Chain won't stay on a RF Turbine crank

    I have a 2x10 Raceface Turbine crank on a Tomac Flint 29r hardtail, with an x9 rear and XT front. My problem is the chain won't stay on the big ring. It shifts fine and is adjusted right. Just about every time I get off the bike in a really nasty section of trail I can't ride the dam chain comes off the big ring. I think a bashring would stop it for doing that. But I can't find one that fits that crankset.

  2. #2
    dirtbag
    Reputation: ranier's Avatar
    Join Date
    Sep 2003
    Posts
    1,444
    BBG makes a bash for your 120 bcd crankset but only coverage up to a 34T outer ring. Other option would be a MRP 2X guide.

    I'm still trying to wrap my head around your problem -

    Quote Originally Posted by pulser View Post
    Just about every time I get off the bike in a really nasty section of trail I can't ride the dam chain comes off the big ring.
    Are you saying you stop at/in a gnarly section, then your chain drops?
    Amolan

  3. #3
    mtbr member
    Reputation: pulser's Avatar
    Join Date
    Dec 2004
    Posts
    1,571
    Quote Originally Posted by ranier View Post
    BBG makes a bash for your 120 bcd crankset but only coverage up to a 34T outer ring. Other option would be a MRP 2X guide.

    I'm still trying to wrap my head around your problem -



    Are you saying you stop at/in a gnarly section, then your chain drops?
    Best way I can describe it is when I get to a nasty section I can't ride. I get off the bike if I haven't crashed and try to quickly get over or around what ever it is. So ether run or walk the bike. Because the spring tension on a 10sp rear derailleur is higher then on a 9sp. The chain comes off the bottom of the big ring and then the crank rotates backwards pulling the chain off. It wont happen when I am riding I think because the crank can't rotate to drop the chain. I have a chain keeper on the frame so it never comes off the small ring.

  4. #4
    mtbr member
    Reputation:
    Join Date
    Nov 2011
    Posts
    1,812
    Does it come off to the inside or outside?
    Is your chain as short as possible?
    What length of derailleur are you running?
    Is there a chainring available with a higher tooth profile? Some middle rings have tiny tooth heights.
    You could try a Bionicon type chain guide. Someone here posted a home made version that might be worth playing with to see if it solves the problem.

  5. #5
    mtbr member
    Reputation: Shalom's Avatar
    Join Date
    Nov 2008
    Posts
    1,994
    If you have a 2x crank, you will not find a bash guard, as there is no place for it. You would need to run 1x.

    If it is dropping off, then I suspect that things are not set up correctly. I also fail to see what spring tension between 10 and 9 speed RDs has to do with this.....unless you are referring to clutch type derailleurs...

    If you are not wanting to make the switch to 2x10, then consider getting a chainguide, like the MRP 2x.

  6. #6
    mtbr member
    Reputation: pulser's Avatar
    Join Date
    Dec 2004
    Posts
    1,571
    Quote Originally Posted by Slash5 View Post
    Does it come off to the inside or outside?
    Is your chain as short as possible?
    What length of derailleur are you running?
    Is there a chainring available with a higher tooth profile? Some middle rings have tiny tooth heights.
    You could try a Bionicon type chain guide. Someone here posted a home made version that might be worth playing with to see if it solves the problem.
    The RD is pulling it off the outside of the crank. It ends up off the ring and hoked on the FD. yes the chain is as short as I can make it. I am running a long cadge RD because I got it on sale. I am thinking about getting a type 2 X9 in a medium cadge to see if that fixes this problem.

Posting Permissions

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