Learn about the tools and methods to perform this basic but often frustrating task that every bicyclist should know. Read on to find out about:
- The basics of pedals
- Necessary tools and supplies
- How to remove pedals
- How to install pedals
- How to troubleshoot common problems
A Few Words About Pedals
When was the last time you’ve thought about your pedals? Unless one of them is giving you trouble, you’re doing some upgrading, or you’re assembling or shipping a bike, it’s probably been a while. While they seem simple, pedals can be very annoying to work with, since they’re attached to a part of the bike that moves freely: the crank. Additionally, pedals tend to tighten up the more you ride your bike, and if they’re really old or installed without any grease, they can become very stuck.
The part of the pedal that has threads is called a spindle, and the rest of the pedal is generally called the body or cage. While there are many styles of pedals out there the most important thing to know about them is that the left pedal is always reverse-threaded, also referred to as having left-hand threads. This means that you will loosen and tighten the left pedal in the opposite direction that you would turn a normal bolt or screw. The right pedal always has standard, or right-hand, threads, therefore you tighten or loosen the right pedal normally (follow the “lefty-loosey, righty-tightey” rule you might have learned in high school shop class, as I did).
Pedals on new boxed-up bikes are conveniently labeled with stickers:
Additionally, most pedals these days are permanently stamped with “L” and “R”, either on the spindle or the body:
However, you might find some pedals have no labels whatsoever, and you still need to know how to tell them apart. Here’s how: hold a pedal with the spindle pointing up. Look close, and you’ll notice that the threads are at a slight angle. If they’re angled up to the right, you’re looking at the right pedal:
If they’re angled up to the left, you’re holding the left one:
The difference is subtle if you’ve never done this before, but correctly identifying pedals is a really good skill to have…and an excellent party trick (just kidding). Another thing to know is that pedals can have one of two different spindle diameters:
- 9/16 inch: standard size used on most adult bikes
- 1/2 inch pedals: used on most kids’ bikes, some cruisers and inexpensive department store bikes with steel cranks, and quite a few older bicycles
These two pedal sizes are not interchangeable, so be sure you know which you’re dealing with before you order those fancy new pedals.
Necessary Tools and Supplies
The majority of pedals can be installed and removed in a pinch with a standard 15mm open-box wrench in your garage, or even an adjustable (crescent) wrench, but I don’t recommend these for two reasons. One, the handle is usually too short to provide enough leverage to remove a pedal, and two, it’s more likely to scratch the crankarm. If you plan on working with bikes a fair amount, a dedicated pedal wrench is a worthwhile purchase. A a basic one like the Park Tool PW-5 costs less than $15, and has a nice, long vinyl-coated handle. All proper bike pedal wrenches will consist of one or two 15mm jaws – narrower than a regular wrench to fit into the tight space between the crank and pedal body – and a substantial handle for good grip and leverage. Park Tool’s higher end models, the PW-3 and PW-4 are longer, heavier, and more durable, and well worth the money if you work on bikes a fair amount. There is also a pedal wrench made just for single-speed and fixed-gear cyclists, the Park Tool SS-15C.
There are pedals that may require a 6mm or 8mm hex wrench. Standard hex wrenches like those in the Park Tool HXS-1.2 Professional Hex Wrench Set are fine, but their short handles might not give you the necessary leverage to remove extremely stubborn pedals. The perfect upgrade is the Park Tool PH-1.2 P-Handled Hex Wrench Set (also available individually in 6mm and 8mm sizes). I love these ergonomic, extra-long wrenches, especially when working with pedals and disc brakes. Park Tool also offers a pair of very sturdy hex wrenches specifically designed for use on pedals and cranks: the HT-6 and HT-8, and the two also come as a set.
Here is a pedal that will only work with a 15mm wrench – the flattened part that the wrench fits onto is called, appropriately, a “wrench flat.”
And here’s a pair of pedals – the silver one will only work with an 8mm hex wrench, while the right one will work with either a 15mm wrench or a 6mm hex wrench:
A note about pedal washers: these are simply washers that are mounted between the pedal spindle and the crank, and they are generally not necessary unless you are dealing with a really expensive aluminum or carbon crank. If you remove a pedal and the washer is there, you probably need to use it again when you re-install a pedal into that crank. Otherwise, you can search for the model of your crankset to find the technical document, and this should tell you if you should use washers. Here’s a link to the Wheels Manufacturing Stainless Steel Pedal Washer.
Pedal Removal
First I want to show you a neat trick that I often use when removing pedals, especially when they’re really stuck. Since the bicycle crank moves, we want to immobilize it in order to make unscrewing the pedal a piece of cake. For this you’ll need a strap, and any non-elastic strap will do, whether it’s of the buckle, cam, or velcro variety. Pedal toe clip straps work great for this purpose! Whatever strap you use, just make sure that you’re able to get it pretty darn tight.
Whichever pedal you are planning to remove, you’ll want to strap the opposite crank arm and pedal onto the bike frame. I prefer using the chainstay (which connects the crank/bottom bracket to the rear axle) as it’s closest to the crank arm and will create the most solid connection:
The seat tube (which the seatpost is inserted into) or down tube (which connects the headset/fork to the crank/bottom bracket) will work fine as well. When possible, run the strap through the pedal itself and around the crank arm as I’ve done here, but don’t worry if you can’t, it should still work:
Hopefully you’ve chosen the correct wrench for the job – the photos below involve the Park Tool PW-3, utilizing the 15mm jaw. Before we crank that wrench with all of our might, let’s stop and think for a moment about which way we should twist the pedal spindle in order to remove it. Remember, as I mentioned previously, the right pedal has normal threads while the left is always reverse-threaded (trust me, you don’t want to get this one wrong!) Check out the illustrations below for a visual guide:
When removing pedals, you want to think about mechanical advantage. This is a fancy term for the clever usage of your muscles, tools, and gravity in order to perform a given task. The reason I’m pushing the wrench downwards is that I’m trying to utilize gravity as well as my body weight. Trust me, sometimes just angling a wrench a few degrees will make all the difference when you’re trying to remove a seized pedal on your grandpa’s 1952 Schwinn cruiser! Or your daughter’s purple Huffy Princess bike, for that matter.
If you’re using a hex wrench to unscrew a pedal from behind, your chances of turning the wrench the wrong are increased, so refer to the photos below. After strapping the left crank to the chainstay, I’m using a normal 6mm hex wrench, and an old seatpost as an extension to provide extra leverage. I’m also wearing a sturdy leather work glove, to protect my knuckles as I apply force to the wrench:
And below I’m working to remove the left pedal, and also wearing a glove:
Remember that even though the hex wrench is inserted from the back side of the crank, it will need to move in the same direction relative to the crank as a pedal wrench inserted from the front of the crank. If this just made you even more confused, just check the photos again.
Most pedals will need a good initial push of the pedal wrench to loosen, so don’t be afraid to really give it all you’ve got! All the while being mindful of your hands, and the bike. After you’ve forced the pedal to move a bit, set the wrench aside and try to unscrew it with your hand. If the going is too rough, by all means keep using the tool, but go slow, especially as you get towards the end of the threads. To finish, undo the last few threads by hand, as this will minimize potential damage to the outer crank threads, and prevent dropping of the pedal. If this is your first bicycle pedal removal, give yourself a pat on the back!
Pedal Installation
First, inspect the crank and pedal threads, and the pedals overall. If the threads don’t look damaged and you’re certain you’ve got the correct 1/2″ or 9/16″ spindle size, and the right and left pedals are correctly identified, you are ready to start. Dab a little bit of waterproof grease (such as the Park Tool Park Tool PolyLube 1000 Grease – PPL-1) onto the spindle:
Start threading the pedal in by hand to ensure the pedal is going in perfectly straight. If the going is rough, make sure once again that you have the correct left or right pedal. If you can’t get the pedal started this way, this usually means that either the pedal and/or crank threads are damaged. Just to be sure, clean out the crank threads with a brush or rag, do the same with the pedal threads, lubricate, and try again.
If you deem that the crank threads are damaged or worn out, there is a neat first-line-of-defense trick that might just help: dab some thin lubricant onto the threads and install the pedal from the back of the crankarm. This might just fix (or “chase”) the threads just enough for you to be able to install the pedal. This is a trick, and there is of course a proper way to do this, with a special tool called a pedal tap. You will need the Park Tool Pedal 9/16″ Taps (or this this cheaper version) and a tap handle like the Park Tool Tap Handle is required. I don’t recommend buying these tools unless you have previous experience with this sort of thing, and have a unique or expensive crank you’re trying to salvage. Even then, this is a job probably better done by your local bike shop and I won’t go into the procedure here. If the threads are not repairable, the shop might be able to replace the threads with an insert, but it’s likely they’ll just try to sell you a new crank, or the left crankarm, if that’s where the damage is.
Troubleshooting: How to Remove a Really Stuck or Seized Pedal
Most pedal spindles are made of steel, and the majority of cranks are aluminum. Metals of different types can corrode and bond chemically over time, especially if the connection was not initially lubricated. If you’ve got a seized-up pedal and no access to a time machine to jump back in time to grease it up, there are a couple of options:
- First, try to remove the pedal with the biggest wrench you have, or grab a pipe or handlebar extension. A seatpost or old pair of handlebars might work. Some extra leverage might be all you need.
- Second, behold the magic loosening power of penetrating oil – Liquid Wrench is my favorite. This is a special liquid that is very thin and slippery, and is designed to work its way in between seized-up mechanical parts. WD-40 will also work, and in a pinch even regular chain lube like Boeshield or Tri-Flow might also help. Here’s how I recommend doing it: lay your bike gently on its side with the seized pedal pointing upwards, then squirt some of the oil around the spindle and into the pedal threads. Wipe up the excess and wait at least 15 minutes, but if you’re working with an old bike with a lot of rust on it, a few hours or overnight is even better. Sleep with your fingers crossed. Then try removing the pedal again.
I have to add that over the several years of owning my bike shop, I’ve encountered a handful of pedals that were so seized onto the crank that no amount of lubricant or force could help. I’d say this probably happens about once a year. In a professional environment, knowing when to give up is a good skill to have, especially since the work is being done on customers’ bikes, and my time (i.e. their hard-earned money) is precious. In your garage, trying to remove a pedal from your beloved old Schwinn Varsity 10-speed bike might be an all day project, and that’s just fine, as long as you reward yourself with a cold beer afterwards!
A Quick Note on Stripped Pedals and Cranks
On a different note, if you’ve just threaded a pedal all the way in and it appears loose, then you probably have a stripped spindle and/or crank. At this point it’s probably time to pay a visit to your favorite bike mechanic.