Quick Answer
You need a crank puller and the right wrench or hex key. Remove the crank bolt, thread the crank puller fully into the crank arm, then turn its center bolt until the arm comes off the bottom bracket spindle. Repeat on the other side.
All biking enthusiasts face this problem at least once in their lifetime. The dreaded crank removal. While it does sound like a scary thing, it actually is pretty easy if you follow instructions. Due to many bikers opting for the wonderful Fluid Nitro bicycle model, this step-by-step instruction will use this model as an example, although the instruction may be applied to practically every other bike model. Before we start, we will explain the purpose of the bike crank and why should one remove it, in case you are a beginner or just want to learn more about the wonderful anatomical world of mountain biking. Enjoy!
The Bike
Why Fluid Nitro Mountain Bike?
You are probably wondering why did we choose this particular bike as an example? The first reason is that the Fluid Nitro bike is one of the most balanced entry-level bikes one can buy. Its lightweight frame, great design that comes in various dimensions, and affordable price make this bike one of the most popular choices for bicycle enthusiasts that have just started enjoying the mountain trails.
Having said that, it is more than likely that these new bikers are in need of some maintenance tips. As such, the most common question all biking professionals get is how does one remove the crank?
Crank Removal Tools
Cranks Explained
What Are Cranks for and How Do I Remove Them?
The cranks are part of the crankset of a bike, which are the “arms” that are located between the pedals of a bike and the chain. To sound a bit scientific, it transfers your leg movement energy into the chains, which further rotate your back wheel. Or in layman’s terms, it makes your bike move, which is the main purpose of the bike and one of the main bike parts that you need to take care of.
It is important to often check your crank, especially after mountain riding. Firstly, do an ocular assessment of your cranks. Check for any dents or other physical and visible damages. Jerk it a few times, if they do not wobble but stay firmly in place, you are good. If everything is alright, clean it all from grime and dirt with a brush or damp cloth, and your bike has been taken care of. However, if you notice that the set has been damaged, and you want to change it on your own, then follow the steps below.
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More Maintenance Guides
Step By Step
Step by Step Instruction on Crank Removal
You just need the crank so you need to detach everything from it. The first step is removing the pedal, which is fairly easy. Just remove the screw that connects the arm to the pedal, and then loosen the pinch bolts. After that, just pull the pedal and it will come off.
The second step is to remove the crank’s center cap. There is a little cap that covers the bolt in the center of the crankset, after removing that cap, clean it a bit before loosening it.
The third step is to physically remove the pinch bolts, the ones that hold the arm to the pedal post and to the spindle. Usually, an Allen key is used to twist the bolts until they are loose before using a wrench to completely remove them.
The fourth step is to remove the washers that are located between the pedal post and the arm of the crank. The washer actually neutralizes the friction when the crank is turned, though not completely.
The fifth step is removing the spindle from the arm. This is a delicate step as the spindle can be easily damaged if mishandled. Proceed with care and do not tug it off, use a wrench or a key if necessary to unscrew.
The penultimate step is pulling out the arm, if everything is nice and loose, you are good to go. Gently pull one side at a time, then lift it a bit before pulling it completely off. While they are off, you can clean the parts on the bike a bit, if you wish.
The final step is putting the new stuff back into its place! You can follow the steps above but in reverse, but here is a quick guide on putting the crank back.
So the first step for putting a new or any crank back into your Fluid Nitro Mountain Bike is to put the cranks into the spindles. The best way is to place the arm pointing at the bottom and slide the first crank onto the spindle, it must be lined correctly, be cautious. If everything is lined, tighten the pinch bolt and replace the compression cap. The second step is the same, but the one pointing at the top is having a spindle slid into it. Again everything must be lined up before tightening the bolt and replacing the cap.
The third step is to screw in the bolt of the crank using a key, after which you tighten the pinch bolts and place the compression cap. The final step is reattaching the pedals to the arms, however, some beginners tighten it too much – avoid this, as it can further damage the whole crankset.
And that is it, you are ready to ride into the sunset and enjoy nature on your mountain bike.
Tools For Mountain Bike Maintenance
A few quality tools let you handle crank, pedal and drivetrain jobs at home.
Repair stand
CXWXC Bike Repair Stand
A folding home workstand that holds the bike off the ground, so cleaning, lubing and adjustments are much easier.
View on AmazonBike cleaner
Muc-Off Nano Tech Bike Cleaner
A fast-acting, biodegradable spray that lifts mud and road grime from the frame, wheels and drivetrain without harming paint or seals.
View on AmazonChain lube
Muc-Off Dry Chain Lube
A wax-based dry lube for dry and dusty conditions. It keeps the chain quiet and shifting cleanly without attracting a lot of dirt.
View on AmazonChain checker
Park Tool CC-3.2 Chain Checker
Shows in seconds when your chain is worn, so you can replace it before it wears out the cassette and chainrings.
View on AmazonCycling gloves
MOREOK Gel Padded Cycling Gloves
Half-finger gloves with 5 mm gel padding that reduce hand numbness and protect your palms in a fall.
View on AmazonTire levers
Park Tool TL-1.2 Tire Levers
Small, strong levers for swapping tires and fixing flats without scratching your rims.
View on AmazonAs an Amazon Associate, The Bike Magazine earns from qualifying purchases. Prices and availability are shown on Amazon.
Frequently Asked Questions
Quick answers to the questions riders ask most about removing a mountain bike crank.
What tools do I need to remove the crank on a Fluid Nitro mountain bike?
You need a crank puller plus the right wrench or Allen (hex) key for the crank bolt and pinch bolts. Remove the crank bolt, thread the crank puller fully into the crank arm, then turn its center bolt until the arm comes off the bottom bracket spindle. A brush or damp cloth is handy for cleaning the parts while they are off.
Is it hard to remove a mountain bike crank at home?
No. Crank removal sounds scary, but it is an easy home job if you follow the steps in order: take off the pedal, remove the center cap, loosen and remove the pinch bolts, take out the washers, then pull the arms off one side at a time. Go gently around the spindle, as it can be damaged if you tug at it.
How do I know if my bike cranks need to be replaced?
Check your cranks often, especially after trail rides. Look for dents or other visible damage, then jerk the arms a few times – if they stay firmly in place and don’t wobble, they are fine and only need a clean. If the crankset is damaged or loose, it is time to remove it and fit a new one.
Do these crank removal steps work on other mountain bikes?
Yes. This guide uses the Fluid Nitro, a popular entry-level mountain bike, as the example, but the same steps apply to practically every other bike model with a similar crankset.
How do I put the crank back on after removing it?
Follow the removal steps in reverse. Slide the first crank onto the spindle with the arm pointing down, make sure it is lined up correctly, then tighten the pinch bolt and replace the compression cap. Repeat on the other side, screw in the crank bolt with a key, tighten the pinch bolts and refit the cap. Reattach the pedals last, and don’t over-tighten them, as that can damage the crankset.
