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Specialized Rockhopper Expert crank- missing left compression end cap, crank fell off

Can anyone advise what the compression end cap is/is like for the left crank on a circa 2015-16 Rockhopper Expert 29er with 2x10 gearing? The crankset is similar to a Hollowtech II, i.e. it is 2 piece with external bearings and two pinch bolts on the left crank arm, but has no markings. Later Rockhoppers seem to have v similar looking ones with the Stout branding so maybe that is it, maybe the markings have rubbed off?

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  • JBAJBA Posts: 2,654
    A quick Google search revealed that both the 2015 and 2016 Rockhopper Expert 29ers were fitted with Specialized Stout XC, 2x10 chain sets.
    Contact Specialized and ask them if they can supply a replacement end cap.

    However, bear in mind that here is a fair chance that if your crank fell off it was loose and has damaged the splines on the spindle. if this is the case you are better off buying a new chain set.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Bird Zero Mk1 ¦ Giant Revolt Advanced 2 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • I had a similar issue with my Stumpy and despite efforts to fit a new end cap and then a new crank arm, the damage was done. The cap wouldn't stay torqued up, the splines were worn and the new crank arm fell off.

    I settled for a new HTII XT crankset and it's be awesome ever since.
    "Ride, crash, replace"
  • The local Specialized supplier says no spares available, the cheapest option seems to be to fit a Suntour square taper chainset, total around £45-50 (I know this will be a tad heavier and not as stiff, but OTOH a UN55 bb will last forever). Next up would be a Deore HTII, around £85 without the bearings, not sure if the OEM bearings will play ball with Shimano crankset and they may be shot anyway, must check.
  • JBAJBA Posts: 2,654
    A Deore M617 chain set can be bought for £35 and the bb about £9.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Bird Zero Mk1 ¦ Giant Revolt Advanced 2 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
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