9. How to Replace Cotterless Crank Arms
Crank removal and installation procedure on a square-spindle, sealed bottom bracket.
This tutorial will demonstrate how to remove and install square-spindled crank arms. I’ve based this tutorial on cranks attached to a sealed cartridge bottom bracket. I’ll cover the loose-bearing style in a future tutorial.
To remove the bolt, you’ll need either an 8mm allen key or 14mm socket wrench. To remove the crank arms, you’ll need a crank puller, a 16mm open-end wrench, and an adjustable wrench. If possible, a torque wrench should also be used for tightening.
In order to safely remove the right side, you’ll have to shift the front derailleur onto the smallest chainring, and then carefully remove the chain and rest it on the bottom bracket, so that it doesn’t interfere with the crank arm removal.
Using the crank arm for leverage, loosen and remove the tightening bolt with your allen key or 14mm socket wrench. Be careful not to skin your knuckles on the chainring teeth.
Before using the crank puller, make sure it is fully extended so that the internal driver does not extend past the external threads.
Note: If crank threads are damaged, there are a few solutions at Park Tools.
Carefully thread the external threads of the crank puller clockwise into the crank arm. Avoid cross-threading, which will damage the crank and prevent future removal.
Once the crank puller is fully threaded, place the adjustable wrench on the external flats and turn the internal driver clockwise until it stops. Turn the driver clockwise using a 16mm wrench, until the crank arm pulls free of the spindle. Repeat the same process to remove the left crank arm.
Before re-installing the cranks wipe both the square spindle and the crank’s spindle fitting to make sure there is no dirt or grease on either surface.
Now slide the right crank’s spindle fitting onto the spindle. Before installing the bolts, grease under the head and along the threads of both bolts. Thread the bolt all the way into the spindle threads and torque the bolt to about 35 foot-pounds, or 420 inch-pounds.
Set the chain back on the chainring and repeat the same installation procedure on the left side, making sure the crank arm is pointing opposite the right side.
Hi, the thread on my crank arm has worn completely away, I have a budget road bike 14 speed but can not find a crank set online can any one help or come up with any alternatives. .. thanks, uk... Read more >>
I was wondering if someone could tell me whether I would be able to fix Power Grip straps to my pedals?... Read more >>
The cruisers right pedal felt slightly askew, it was late and only a mile from home. I gave it a cursory inspection, I'd check it at home on the stand.
I gingerly rode on a few revolutions and BAM!
1) Right foot slams to the ground and pushes forward off the toes
2) Gonads pound into the nose of the seat
3) Chest hurtles towards the the bars
4) Body rotates slightly to the right as the right foot is dragging
5) Left foot tries to slide outwards off the studded pedals
6) Every ounce of strength in my being tries to lock my shoulders, pecs and bic... Read more >>
Haven't rode in years, just bought a new MTN Bike and the pedals are a longer distance apart than I was used to.....I want to replace the crank arms w/shorter ones and are the fittings universal? and where can I purchase them?... Read more >>
Hello, I just got this bike. I paid 50 bucks which I thought was fair. It is a Giant Acapulco probably from the late 90s/early 2000s. The bike functioned well until today when I felt the pedal wobbling and the pedal fell off. So I was reading a few other forums and they said that the crank arm was most likely the problem. The nut also appears to be stripped. So my question is should I just go to a bike shop and get a new nut or should I just order a crank arm set off of ebay. Also if I order a crank arm off ebay which one should I get. I am looking to spend under 30 bucks for this sinc... Read more >>
Got the Sram red chain rings. Definate difference. The shift is quicker and it does not hesitate at all. Feel much more confident in the bike now. Feels real good. Took it to a park in the area where there are some real twisty trails and quick up and down hills. It requires a good bit of shifting and it really performed well. Super fun ride! Am happy to put this chapter behind me and now just ride!
Bill... Read more >>
There is this random clicking nose that sounds like it's coming from the crank shaft possibly. As I pedal you can hear a clicking noise as if two pieces of metal are tapping each other. It's kinda rusty back there as I had to leave my bike outside during the winter.
What does someone recommend I do?
Thanks.... Read more >>
I have a folding bike with 7 speed freewheel in the back. My front crank needs changing. I have seen one but it will only run a single speed 1/8" chain. My question is can I run a single speed crank & chain with a 7-speed freewheel?
Thank you in advance for any help.... Read more >>
As you may remember,I am having a big prob with fd shifting up from little ring to big ring.bike is back in the shop at this time. They are thinking that the trouble is the fsa crank and rings. The rails are notbuilt like the sram and shimano. The cervelo has Rival on it w/fsa crank. we are talking about upgrading at shop cost for materials to shimano crank. I guess my question is do i want to replace the whole crank or just the rings? What would be the advantage to a complete replacement? I was thinking about replacing the rings with red an see what happened.
Than... Read more >>
This has might of been already been said, but my crank is wobbly, I've tightened the bolts on both sides, but in truth they were already tight!?
Do you think I need to replace something?... Read more >>
I need to service and or replace the Raceface ISIS drive bottom bracket on my bike.
I have the drive side crank removed, abd even have the drive side BB cup off...however I am unable to get the other (non drive side) crank arm off, the bracket bolt will not budge. And I can not get the drive out.... what do I do?... Read more >>
I hope I'm posting in the right place.
So as I was riding this morning, I noticed my pedals starting to loosen.
Upon closer inspection, looks like the entire crank is loose, but I have no idea how to retighten it.
(ignore the cord in the second image, those are my headphones)
In the fourth image, the ball bearings are exposed.
Thanks!... Read more >>
I saw this seller selling these single speed cranks on Ebay as per link below.
How do you go about choosing the correct number of teeth crank f... Read more >>
I have a Dawes 1500, under a year old and started hearing ¨popping¨coming from the crank área. I´ve ridden the bike pretty much every day for the past 3 months since I moved to mexico. I now have some minimal lateral movement in the crank área and was wondering on lets say ¨average¨cost for a repair like this, if there is such a thing. I don´t want to get railroaded when I take it to the bike shop here. Also, in the future could using clip on pedals be better instead of my current straps. I am riding alot of hills and standing for a good part of the ride. Thanks for help and for... Read more >>
my first post on here
Was just given a carrera subway 2, which needs crank replacing. The thread on the crank that holds the pedal is worn and can keep the pedal on. So, I need to replace it. When I looked at it, I notice that the bolt that holds the crank to the bottom bracket is actually not a normal bold, but an Allen Wrench Hex key one. So, my question is if the procedure for removing and replacing the crank wil be same as with other ... Read more >>