My experience is that those bolts are hollow and you can access them from either side. Is that not the case for you?
crabcrabcam on
You should just be able to pop the allen key into that one. It’s just backwards to the others (and has no outside nut, as that’s the crank arm)
PoisonIvyPrince on
You’ll need a tool to hold the nut. Park Tool makes one: the CNW-2. If you can’t get the actual chainring nut tool to the backside of it, use a paint can opener like you can get from any hardware/home improvement store to hold the nut.
joshrice on
If it won’t loosen with a key on this side, there should be a slot on the crank/outside of that bolt you can wedge a flat head into (there is a special tool for this) to hold it and prevent it from spinning.
Isn’t it a chainring nut in that gap? Meaning that the bolt and nut are reversed compared to the other four.
Often you can remove these without holding the nut, but if necessary you can use the regular chainring nut tool to hold.
RandoMrShwifty on
Yes, it’s standard on modern Shimano cranks and the bolts in your photo appear to have been installed incorrectly.
BikesMapsBeards on
On some cranks there is a “hidden” chainring bolt positioned behind one of the crank arms. The nut portion press fits into the chainring. You should be able to remove the bolt portion and disassemble normally. For reference, just Google ‘hidden chainring bolt’. If you’re replacing chainrings you’ll likely need a new one since they are a pain to remove.
8 Comments
My experience is that those bolts are hollow and you can access them from either side. Is that not the case for you?
You should just be able to pop the allen key into that one. It’s just backwards to the others (and has no outside nut, as that’s the crank arm)
You’ll need a tool to hold the nut. Park Tool makes one: the CNW-2. If you can’t get the actual chainring nut tool to the backside of it, use a paint can opener like you can get from any hardware/home improvement store to hold the nut.
If it won’t loosen with a key on this side, there should be a slot on the crank/outside of that bolt you can wedge a flat head into (there is a special tool for this) to hold it and prevent it from spinning.
This is the tool if you need it – [https://www.amazon.com/Park-Tool-CNW-2-Chainring-Wrench/dp/B000OYFF2K](https://www.amazon.com/Park-Tool-CNW-2-Chainring-Wrench/dp/B000OYFF2K)
Isn’t it a chainring nut in that gap? Meaning that the bolt and nut are reversed compared to the other four.
Often you can remove these without holding the nut, but if necessary you can use the regular chainring nut tool to hold.
Yes, it’s standard on modern Shimano cranks and the bolts in your photo appear to have been installed incorrectly.
On some cranks there is a “hidden” chainring bolt positioned behind one of the crank arms. The nut portion press fits into the chainring. You should be able to remove the bolt portion and disassemble normally. For reference, just Google ‘hidden chainring bolt’. If you’re replacing chainrings you’ll likely need a new one since they are a pain to remove.