No excuse not to have one. Ok, sure, you can remove the crank without one. But that relies on impact force and. Good Luck. I think of using impact techniques in bicycle assembly or disassembly as like surgery on the human body.
Surgery is invasive and only ever a last resort. Slow consistent pressure, building slowly then releasing slowly is usually always the best approach. One of the better ones. He uses a screwdriver as a wedge in between the lockring face and the crank.
Tapping it has the effect of squeezing the crank away from the spindle. A slip of the hammer, screwdriver or, heavens forbid, cold chisel!!! He makes it look easier than it is. You really have to have the right touch and there is a learning curve involved to get that touch. The big end on the left screws into the crank—your crank has threads cut into the spindle aperture and the puller will fit right in. Here the foot is fully extended. But you get the idea.
I use one of these for that very reason. Nothing much to it really. Or read on. We cover the whole process below. Firstly, remove the crank bolt with the 8mm wrench. Screw it out as far as it will go. Then install it into the crank. As with any threaded tool or component that you need to always be mindful not to cross the threads.
This thread is conventional right-hand thread so seat it correctly in the crank threads. It also does not hurt to apply some light oil, sewing machine oil, that sort of thing, to the threads. Light lubrication ensures easier installation and removal, as well giving the most resistant-free experience in turning the foot bolt and pressing the crank away from the spindle.
A 15mm socket wrench is the best tool to use. A socket ratchet wrench is the most convenient of course. Or ring spanner. Basically you want to be using a tool with the longest handle possible. That way you will get the leverage required for the intial turns. A crescent wrench will be fine also, but more likely to slip given the amount of force required at the very beginning of this procedure. Nevertheless, a big crescent wrench with a long handle will give you more leverage than alternative, shorter handled, tools.
The crank will likely be fitted tightly. Breaking it free will require a lot of elbow grease for one-half to maybe one full turn. Once it breaks free, then it will come off easily and quickly. You will probably only have to move the crank a few milimeters. Then it will come loose and slide right off.
In this shot the crank is almost right at the end of the spindle. Make sure you are watching carefully. The crank can come free so quickly it may fall to the floor. The drive side, being heavier, is more likely to get away from you in this manner. Once you have removed the crank simply remove the crank puller. The non-drive side is removed in the same fashion. Now, the procedure will be hugely more complicated if the crank has rusted onto, or fused in some way with the spindle.
Not using grease in the initial installation makes it more likely to happen. Applying grease to either the spindle taper, the crank aperture surfaces or both is a controversial topic. However, as with all components a key reason for applying grease is to make the job of removal easier—or simply just possible—later, often many, many years later.
Check out the article to survey the various opinions on the subject. Installing the crank on either side is straightforward. Practically speaking, this means that the procedure is not the reverse of crank removal. You can start with either side. I normally begin with the drive side. You install this first then finish it off by attaching and tightening the non-drive side arm. With a square taper crank, you simply need to slot the square aperture in each to the spindle.
The important thing here is to get each square ie. Not so for square taper. A friend once had his bike serviced before a big community ride which included crank removal and bottom bracket servicing. No ride for him that day. I never asked him how he never noticed this when he picked up the bike. I mentioned this earlier. Some do grease it. Many swear off it. Just like lube on the chain actually. But just watch anyway. Make sure the crank bolts are greased.
Grease will give a more accurate torque reading and ensure you can remove them when the time comes. And it will. Put the bolt in place and tighten a little. You will not be able to get it really tight because you need to grip the opposite crank when tightening to torque tolerance. Apply a minimum of 35 nM Newton Meters.
Maxmimum 45 nM. Even with a long-handled torque wrench, achieving 45 nM will be challenging. Install each crank on its spindle. The procedure for installing a Shimano Octalink crank, is exactly the same. You just have to make sure the crank sits snugly in the splines. Also ensure the the non-drive side crank is on the same one hundred and eighty degree plane as the drive side. These caps are resistant to sitting snugly in position when new. It will take a few goes to get it right. Once they loosen up it will be easier to seat them.
They will slot right into place on an older crank. Make sure the dust cap is in exactly the position you want it to be before you press it in. Then repeat the procedure. To remove simply lever the cap off with a narrow, sharp ended tool. Slip the tool under the slight gap at the top. Lift the cap slightly. If the BB is an old one, been in there for a long time, then that initial movement will be hard to get even if you have liberally applied penetrating fluids over an extended time period.
That long handle allows maximum force with minimum effort to get the BB turning and on its way out of the shell. This wrench also has the half-inch drive that connects to the BB tool—the guesswork is taken out of tightening your bottom bracket to tolerance. The first thing to do is loosen then remove the non-drive side lock ring. For a bottom bracket that has been in place for a long time, you may need to use some penetrating fluids well in advance of attempting the removal.
The lockring will probably not be as tight as the drive-side which, because it is the drive-side, tends to be tighter. If the square taper bottom bracket in question has a nylon lockring , it will likely not be very firmly seated in the BB shell.
You have to make certain the tool is perfectly fitted to the lockring, otherwise it may slip. The teeth will be damaged making it harder to remove and re-install. Once you break the lockring free of the BB shell, continue to remove it with the tool and having loosened right up, complete the removal by hand.
The drive-side is the crucial side of course since that constitutes the cartridge bottom bracket as a whole. Using the wrench employed to remove the left, non-drive side lockring, may work. But the drive side of a bottom bracket is generally tighter than the non-drive side. So be prepared for a challenge. In the shop here are all sorts of bits and pieces, including a number of seat posts.
A seat post, or basically any type of narrow-gauge pipe, will do the trick. By lengthening the wrench handle you increase the leverage exponentially. Only bottom brackets corroded into the BB shell resist this assault. An old torque wrench can do the job. The combined leverage of the longer handle and the high torque setting will be enough to break all but the most stubborn bottom brackets free of their shell.
Or should be. To avoid possible damage to the wrench, make sure that the torque setting far exceeds the degree of force required to loosen the bottom bracket enough so the removal can be completed easily. In many cases the factory installed the BB with a pneumatic tool without regard for maximum torque limits. That often explains why some bottom brackets are hellishly hard to break free.
Bigger shops will likely have a pneumatic tool and driver to do the job. Anyway, using a large wrench like this one is by far the easiest way. Once you have broken it free all that remains is to continue to turn the bottom bracket cartridge and remove it from the bb shell.
Once the old bottom bracket is out, cleaning the bottom bracket shell is essential. Get rid of the old grease. A really, really, really. The threads may have been slightly damaged on removal, or simply never been tapped by the installing mechanic in the first place, a heinous sin if ever there was one.
Frame manufacturers outsource bottom bracket shell thread cutting to specialists who do a first-rate job. Still, tapping and facing.
That may make seating the bottom bracket exactly into the right track in the threads very difficult. When re-installing the old BB or a new one the result may be a cross threaded BB. A tapping and facing tool is quite expensive. You or your bike shop guy need to take extreme care for this stage.
If the bit is not seated exactly in the threads correctly from the very start, you will ruin them. There will be immediate resistance. If you cut, you will be cutting incorrectly. In this first stage just turn the bits into the bottom bracket shell just enough that they are supported by the shell. Once the bits are properly seated they will turn smoothly, effortlessly even. Any resistance after this stage, however, means the threads need to be cut.
The bit will both rotate easier and cut more keenly. Easy turning will help in spades should the threads really need cutting, which they will if they are damaged. If there is any resistance, this means the shell threads need to be cut. Rotate into the cut for one or one-and-a-half turns. Then reverse direction, loosening off. Continue to turn the bits into the bottom bracket shell until each is fully inserted. When each bit has reached the limit inside the BB shell, smoothly turn the bits in the opposite direction to remove them.
Make sure you get the removal process right. You need to support the tool and the bits as they approach the BB shell edge face and as you remove them. If not then a bit will drop away from the BB shell as it exits and damage the threads at the very edge. You will be much more likely to cross-thread the bottom bracket as you introduce it to those initial threads since there will be resistance from those damaged threads.
That means forcing the bottom bracket threads to sit seemingly correctly in the BB shell. Having successfully removed the tapping tool from the BB shell, you need to clean any detritus or aluminum shavings from any thread cutting. Give the shell a brush then a wipe with a shop cloth or rag. Applying grease to the bottom bracket shell along with the bottom bracket cup threads is extremely important. At the very least, removing the bottom bracket in the future will be infinitely easier.
And there will be less wear and tear. A pair of nitrile gloves for handling the grease is a good idea, especially if you are keen on keeping greasy finger marks off the frame when doing subsequent work. Give the bottom bracket shell a liberal coating.
More is more in this case; no harm done in applying more than you think is necessary. Use degreaser if you have some handy. Begin with the square taper bottom bracket complete unit on the drive right side.
Fitting the bottom bracket threads exactly to the BB shell threads is crucially important. Too easy to think you have got it right, begin turning. Use a tool without a wrench to do this. If you need a wrench at this stage it is more than likely you have cross-threaded the bottom bracket into the shell—trust me on this. By continuing to force the bottom bracket you will ruin the threads which will mean they will have to be re-cut.
A robust tapping tool is what you will need to complete that task. In the event, reverse the procedure, remove the BB and carefully inspect the threads. If there is no damage that means the installation requires more leverage than normally would be the case. With caution. When you feel the BB seat into the thread, reverse direction ie. Grease the lockring. Now install the lockring in the non-drive side.
Turn it is as far as it will go by hand.
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