• 09-29-2017
    ekraft84
    Sram Eagle - Swapping Crank Arms
    Picked up a new bike recently, with the Eagle setup. Awesome, great, etc. It's a 175 crank though and I'd like to go 170.

    I'm not even sure how possible/cost effective this would be, but is there any way to find just the arms anywhere?

    Does anyone want to buy a 175 Eagle crank? :)
  • 10-12-2017
    Cleared2land
    Why is a reduction of 5mm important enough to warrant the expense?
  • 10-12-2017
    mfa81
    talk to tour dealer, they should be able to make this happen for little cost if you are buying a new bike!
  • 10-12-2017
    acedeuce802
    You'd just buy a 170mm Eagle crankset, in either GXP or BB30 depending on your frame. The drive side crank arm is one with the spindle, so it's not like you would just buy the arms. If you really want 170mm, see if the shop will do a swap. If you can live without being able to ride for a bit, you can always list your current crankset for sale, then when it sells, ship it out and buy a new crankset with the money earned.
  • 10-13-2017
    Cleared2land
    2 Attachment(s)
    Quote:

    Originally Posted by acedeuce802 View Post
    The drive side crank arm is one with the spindle, so it's not like you would just buy the arms. If you really want 170mm, see if the shop will do a swap. If you can live without being able to ride for a bit, you can always list your current crankset for sale, then when it sells, ship it out and buy a new crankset with the money earned.

    While your advice is sound and perhaps the best route to a crank swap, your information is not correct.

    The drive-side and non drive-side crank arms can be separated from the spindle.

    Attachment 1162184

    Attachment 1162185
  • 10-13-2017
    acedeuce802
    While I don't know 100% if the crank arm can be separated from the spindle, it's not common practice, and they don't sell just the crank arms. It's not like there's a spline and simple nut on both sides of the spindle, one side is intended to be removed, one side is not. The pictures you posted only prove that GXP cranks have the spindle fixed to the drive side, and the non-drive side gets removed for assembly, and BB30 cranks have the spindle fixed to the non-drive side.
  • 10-13-2017
    Cleared2land
    You are incorrect in your assumptions that the spindle can not be separated from the drive-side crank arm.

    I have done it. I had a crank that was creaking and it was discovered it was an under-torqued drive-side crank arm bolt.

    The drive-side can be just as easily removed and reinstalled from the spindle as the non drive side can be. There is no stated preference for removal.

    SRAM outlines this in their MTB Cranks and Bottom Bracket Manual. It takes an 8MM Hex and is torqued to 54 N-m.

    You are correct about how they sell their cranks, and I agree that is the best way to go about the OP performing this task. However, technically you're incorrect on the assembly/disassembly of these components.
  • 10-13-2017
    acedeuce802
    Maybe you have a different style of SRAM crankset. There is clearly no 8mm hex on the drive side crank of the GX Eagle crank pictured below (and not on my XO crankset either). Looking through the manual, there's nothing that indicates that both sides can be removed.

  • 10-13-2017
    Cleared2land
    Yes, yours does look different.
  • 10-30-2017
    Schwa72
    The spindle on the GXP cranks is permanently attached to the drive-side crank arm. The spindle on the BB30 cranks is permanently attached to the non-drive-side crank arm.

    To the OP - I've yet to see the Eagle crankset offered without a chainring. However, the complete Eagle GX crankset is only ~$100 so it's not like omitting the chainring is going to save you much money.
  • 01-15-2018
    Haymarket
    Does anyone know if the Eagle cranks actually get shorter arms from one length to the next, or are the holes in these just drilled at different lengths? I want to move to 170s to cut down a bit on pedal strikes, but I know some cheaper cranks donít actually have shorter arms. Just different hole locations.