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Crank Removal and Installation - Three Piece Crankset (Square Spindle, ISIS, Octalink) - YouTube
Channel: Park Tool
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Hello, Calvin Jones here with Park Tool Company.
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In this video we're going to walk through the process of crank removal and installation for three piece cranks.
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If you're not sure what type of crank
system you have, watch this other video
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and you'll be guided to the
proper removal and installation process.
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Otherwise, thanks for joining us and let's begin.
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First, before we get into the process, let's give you an overview and a look at what goes on inside.
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We've cut away part of the arm so you
can see inside so we can follow the action.
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We take the bolt and remove it counterclockwise.
It's going to come fully out.
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What we can see here is that the
arm is fitted over the spindle.
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Now even though the bolt is out completely,
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if we grab the arm it's still not
coming off - its still held tight to the spindle.
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What's required is a crank remover.
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A crank remover has a threaded coupler that goes into the threads of the arm.
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It's fully engaged, and then the spindle driver is going to come in, contact this outer edge of the spindle.
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We can see what's going to happen
if we continue to turn the spindle driver:
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It's going to take the arm
and pull it away from the spindle
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pushing against the spindle end, pulling with the arm, continuing until it comes fully off.
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The tool is going to be removed from this arm
and the process is reversed on the other side.
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Arms going back on are fairly simple:
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the crank bolt is going to go in place and it's going to act as the press to push that arm back onto the spindle.
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Here we are engaging and shoving the arm over the spindle. That is what holds are cracks to the bike.
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Now we've seen that, we're going to need a
wrench that's going to remove the crank bolt or nut,
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a crank remover to extract the arm from the spindle,
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we're going to want lubrication and a rag for cleanup,
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and a torque wrench is highly recommended for the
high torques that we see in the three-piece cranks.
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Crank arms are removed in order to replace them. They're either worn out, damaged or maybe you're upgrading.
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You may want to service or replace the bottom
bracket bearings between the arms.
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It's also easier to do a thorough
cleaning when the crank arms are off the bike.
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Step one is always to remove the crank bolt - but sometimes there's a dust cap that's in the way.
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This one has a simple pressed-in dust cap.
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A straight-bladed screwdriver pops out the
dust cap and there is the crank bolt under it.
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Sometimes it will be a threaded dust cap. In this
case we take a pin spanner, loosen the dust cap,
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turn it, and underneath the dust cap is the bolt.
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However, there are also self extracting crank systems.
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Here - do not remove this ring, it is not a dust cap.
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The self-extracting systems are
explained in more detail in another video.
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Now let's walk through the full process.
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Let's begin with this crank arm
by removing the crank arm bolt.
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As always, when we work we should consider our body position and our hand and wrench position.
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This is good mechanical advantage.
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If I happened to have gone here, that's
very poor mechanical advantage.
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I can always spin things around
and find different ways to hold.
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Now I'm ready to loosen counterclockwise.
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The bolt comes out...
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and we should always look inside
in case a washer was left behind.
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Pull this washer out. It must come out
before any crank extractor goes in.
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The bolt that we've removed is going to let you determine the style of tool that's going to remove the crank.
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The smaller 8mm bolts - about the size of a pencil use the small driver foot of the CCP-22
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or the small foot on the CWP-7 to safely push against the end of the spindle.
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The larger bolts of the Octalink or ISIS Drive
use the larger foot of the CCP-44
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or the large foot option on the CWP-7 to safely
push against the spindle of their system.
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This was the bolt that we removed from the bike -
let's get the tool and get to work.
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In our case we want to back up the driver
fairly even with the threaded coupler.
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Now we are going to install and screw in the threaded coupler,
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making sure it's not cross-threaded
in the crank arm as we do so.
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Screw it down by hand all the way
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it's also a good to get a little extra pressure there
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to make sure we have full thread
engagement of the threaded coupler.
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For the nut-style spindles,
the crank is held on with the nut.
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Notice the spindle protrudes past the flat in the crank.
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Make sure the spindle driver is well
backed up into the threaded coupler
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so that you get full thread engagement
of the coupler into the crank.
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We're now ready to turn the spindle driver downward until we feel it contact the end of the spindle.
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Here again, think about your good mechanical
advantage - move the wrench as you need
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and your hands until feels more
comfortable and begin pressing.
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Little bits at a time are fine - we are walking
the crank off the spindle.
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Keep going - it's eventually going to
get easier and easier and now almost ready
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It is coming off by hand and we will repeat the process
on the other side.
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Installation should begin with surface preparation.
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Anti-sieze or grease should always be applied to the threads of the bolt. This helps that pull up fully tight.
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Greasing the spindle service is also an option especially if you're in an area of corrosion and rust.
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What keeps cranks from creaking,
however, is tension from the bolt.
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When installing the arm, check the fitting on the spindle that it is correctly clocked to the fitting on the arm.
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Slide the arm in place and now thread in the bolt.
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Correct tension is very important for the three piece crank.
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Manufacturers' recommendations go from 30 Newton
meters to 45 Newton meters - a very wide range.
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This is why a torque wrench is always appropriate.
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Consider your mechanical advantage and begin working the bolt all the way in.
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The wrench has clicked - we're now at full torque for this brand
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this crank is fully installed.
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If you're using a hand wrench, you're going to have to use what's called perceived torque
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or the amount of effort you're putting on that wrench.
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Here I am holding the ranch about 10 inches from the bolt.
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This is a 350 inch pound recommended torque -
that is about 35 pounds of effort on this wrench
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so I am giving it a good healthy push to be fully tight.
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Thread preparation is repeated on the opposite side.
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The arm is placed 180 degrees from the first arm installed. The crank arm bolt is installed.
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This side will be pulled equal torque to the first side.
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And those are the basic procedures for
removing and installing the three piece crank.
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For more information visit the repair help section of parktool.com. Thank you for joining us.
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