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Tools for crank and bottom bracket removal

rumbatazrumbataz Posts: 796
edited January 2016 in MTB workshop & tech
I want to be able to service the cranks and bottom bracket on my hybrid bike - a GT ZUM S2. I've watched a lot of YouTube videos about this and the process itself seems to be fairly straightforward. However, I don't know what tools I'll need to do this as there's all different types of cranksets out there.

From what I know, the GT ZUM S2 hybrid bike has a Suntour XCCT chainset. I don't know much about the bottom bracket but I believe it's a sealed unit and square-taper design.

On the crank arms there is some kind of cover with what appears to be an 8mm hex hole so I guess that I can use my 8mm hex key that I bought for pedals to remove this? However, I don't know what tool I need after that - some kind of crank puller?


  • The RookieThe Rookie Posts: 27,811
    They may have a self extracting sleeve so that as you undo the 8mm it will pull the cranks off, or you may need a crank puller, you will also need a standard BB tool.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
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