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New groupset on 2005 HT stumpjumper

I've got a 2005 hard tail stumpjumper that I use as my daily hack riding to work. It's done a lot of miles and needs a total overhaul. I've also got a 2018 Specialized Enduro, but find the gearing sadly lacking with only 42 tooth big cog at the back and some serious techy climbs round here. Would love to upgrade the groupset on my Enduro and use the 1x I take off on my old stumpjumper as gearing would be perfect for the commute. Is it even possible, or is a 2005 frame and wheelset so different as to be impossible?


  • Not impossible but you need to know a few things like what both front cranks/bottoms brackets you have to see if they are compatible and the 1x can go on the Stumpy.

    The rear gearing is a similar question. Your stumpy might be 3x9 if original kit? Is your 1x 1x10 or 1x11? If Shimano - the cassette should fit on your hub. I'm no expert on that so you should get a better opinion. If your Enduro is SRAM and you have Shimano on the Stumpy, the cassette won't fit. If both are Shimano - it should work.

    Get a 2nd opinion on that though as I'm making a few assumptions.

    I've got a 2006 HT Stumpy and it's been a great bike. Originally had Truvativ crank and GXP bottom bracket. That all got changed to XT and Hollowtech II bottom bracket and much preferred it. The rear was always Shimano anyway and got a new XT 3x9 setup 4 years ago. I've just transferred most of it to a CRC Brand XT HT frame as my Strumpy was a M and a bit too small for what I ride now. It climbed like a goat but 90mm forks, a small cockpit and older geometry just wasn't working. The new bike is heavier but now more an aggressive HT. It's running 140mm forks as well and just love it (Stumpy frame and forks reside in the shed as nostalgia items).

    If you post the details of the gears, cranks and bottom brackets on both bikes, we might be able to help more.

    "Ride, crash, replace"
  • Thanks for the help. Sounds like it's going to be a real longshot. This is the spec of the Enduro:
    Rear Derailleur SRAM GX, long cage, 11-speed
    Number of Gears 11
    Shifters SRAM GX, trigger, 11-speed
    Chain set Race Face Aeffect alloy crank, 24mm spindle, 28t direct mount ring, 6000 series alloy Steel, 28T
    Bottom Bracket Race Face PF30
    Cassette SRAM XG 1150, 11-speed, 10-42t
    Chain KMC X11, 11-speed w/ Missing Link™
    Rear Hub DT Swiss 350, Star Ratchet, 36t engagement, SRAM XD driver body, 12mm thru-axle, 148mm spacing, 28h

    Stumpy has original 3x9 shimano lx/xt setup. Guessing bottom bracket is shimano. Hubs and rims probably not worth saving as they've done a lot of miles.

    Interestingly mine is a medium and should ride a large. Would have preferred to spend the money on upgrading the Enduro and passing the bits down to my stumpy, but suspect the stumpjumper should be retired as requires too much money spending on it. Shame as it's ideal for commuting to work, even if the geometry is a bit strange.
  • The RookieThe Rookie Posts: 27,748
    The cassette won't fit as it's XD driver compatible
    The chainset may fit using a PF30 BB threaded, but the chainline will be boost and wrong for your Stumpy.
    Shifter and rear mech will work but you'll need a Shimano cassette (MTB or road with a 34T sprocket), you can probably re-use the chain.
    Wheels won't fit as they are boost.
    Just do up your stumpy using decent used parts off evilbay.
  • JBAJBA Posts: 2,719
    This shouldn't really be in FAQs.
    You'll probably get more views and responses if you move it to MTB Workshop and Tech.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Sonder Broken Road 2021¦ Giant Revolt Advanced 2 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • I agree with The Rookie. I wouldn't give up on it - you can pick up the required bits and keep it going. Maybe just sell off the Enduro parts and use that to fund the Stumpy upgrade?
    "Ride, crash, replace"
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