Guide to Stripping Bikes and Sorting Parts

Introduction

Often at the Bike Kitchen we strip down bikes that are severely broken or unlikely to be reused. The components that we strip go into the digging stream so people can use them to build up other bikes. Also, when you're completely overhauling your own bike, you start by stripping it down, but it's the former case we're most concerned with here.

It is also worth noting that to strip or not strip a bike has its own issues :

• usable components don't get stripped and end up in metal recycling
• components that are not reusable often make it into digging stream
• components are often stripped or made incomplete, also making them unusable.

Why Do we have this guide ?

We often have untrained volunteers strip bikes. This has leads to some problems:

• Usable components are left on the frame and are thus lost when the frame is recycled
• Non-usable components are put into the digging stream
• Usable components are themselves taken apart, making them non-usable
• Volunteers do not learn how the different components are put together and work, defeating the purpose of having them strip the bikes

We therefore wrote this step-by-step guide to stripping a bike for the uninitiated. You'll need some bike vocabulary to get it. One of the best places to look up such vocabulary on-line is Sheldon Brown's Glossary of Bicycle Terms.

To some extent, these steps can be re-ordered. Depending on the condition of the bike that you are stripping, you may also skip some steps. The order below is the ideal one to follow. Perhaps one day we will add some photos to make this more interesting and useful.

When do you strip a bike ?

The easy answer is, "When it makes sense." There is no hard and fast rule about stripping a bike, but you could apply the following rules:

• Can the bike be built up by a member starting "as is?" → The bike should not be stripped.
• Does the bike need parts removed just to get it working, as when major components are broken? → Such components should be stripped.
• Does the bike have unique parts that should stay together and with the frame? → These should stay on the bike.
• Will the bike get used as is, or do we just want the parts? → If the frame is unlikely to be claimed (for example, if it is a very unpopular style), we may remove components even if the frame is re-usable.
• Is the frame junk? → Strip it.

If you are unsure whether something should be stripped, ASK!

A note on tools

As a glance around the Bike Kitchen will tell you, bicycle mechanics rely on many specialized tools to take bikes apart and put them back together. This variety exists because there have been so many bike makers and bike styles over the years, and because standardization within the industry isn't what it could be. Mechanics with several years experience are still known to pick up a tool and ask, "What's this for?" or to look at a particular style, say, of bottom bracket and ask, "Is there a tool for taking this off?" This is normal.

We mention this because it's the impulse of new mechanics to try to disassemble new bicycles with many of the tools found in a home toolbox: screwdrivers, hammers, pliers et cetera. You only use screwdrivers on a bike to tighten or loosen screws, and you almost never use hammers or pliers. In particular, using pliers to tighten or loosen bolts is a good way to strip those bolts and make them harder or even impossible to remove.

Simply put, there's a tool for it! Whether it's an adjustable wrench or (ideally) box wrenches rather than pliers, or a tightening jig rather than a mallet, a tool and method usually exists to remove stuck-on parts without damaging them or the rest of the bike. Learning which tools to use when is a basic part of becoming a skilled bike mechanic. Therefore, if you ever have any questions about what to use when, ask. We are happy to tell you.

The process

Accessories

Accessories include any parts that are not essential to the basic operation of the bike. Some examples include:

• Lock mounting brackets
• Cycle-computer mounting brackets
• Water-bottle cages
• Racks
• Seat bags
• Light mounting brackets
• Mirrors
• Bells

Get these out of the way.

Sorting

If the accessories are complete (light mounts with lights; computer mounts with the computer, the sensor, and the magnet et cetera), bundle them up and file them with similar complete accessories.

Disposal

If the accessories are incomplete, throw them away or recycle them.

What do we do about water-bottle cages and racks? 
They are almost always complete but we don't seem to store them.

Cables and Housing

Most bikes have up to four cables that each run through one or more lengths of housing: one for each brake and one for each shifter. Removing the cables and housing makes the rest of the stripping job simpler and cleaner.

Removal

• Trim off the any aluminum cable crimps at the ends of the cables (These will be projecting out past the brakes and derailers) using the cable cutters.
• Loosen the anchor bolt that holds the cable to the derailer or brake.
  • Do not completely remove the anchor bolt!
  • Note that center pull brakes and cantilever brakes, described below, have short auxiliary cables to which the main brake cable is attached. These shorter cables need to stay with their brakes and should not be removed at this stage. See the section on brakes for more information.
• Pull the cable through the anchor bolt
  • Trim off any frayed or crimped end using the cable cutters.
• Slide the cable through the housing.
• Cables have molded ends that are held in place within the brakes and shifters. Once the cable is loosened and pulled out of the housing, try to extract it from the brake or shifter to which it is attached. If you don't know how to do this, ask a mechanic.
• The housing should come out of the frame easily. The exception is on the various types of taped handlebars (drop bars, mustache bars, longhorn bars and butterfly bars) where sections of the cable housing may run underneath the handlebar tape. In this case, remove the tape at this point.

Sorting

• If the cables are in really good condition, you can usually save longer cables like the rear brake and derailer cables. The same goes for longer pieces of housing. This is not a place to be over-zealous, though. Cables and housing are meant to be replaced at semi-regular intervals. In particular, if a cable is corroded, kinked or frayed, it should be recycled.
• Coil up all cables tightly so that they won't unwind into a big mess. This includes any cables to be recycled.

Disposal

• Waste cables can go in the metal recycling.
• Waste housing goes in the trash.

Wheels

Take off each wheel

• If you have already removed cables then the brakes will not be in the way; if you have not, then you will need to loosen the brakes to get the tire past the brake shoes.
• Ensure that the quick-release skewer or axle nuts that held the wheel to the frame remain in place.

Inspect the tires

• Are they worn out?
  • Are the side walls failing? This means that the canvas or nylon threads have begun to fray, not merely that the rubber on the side walls has begun to crack.
  • Are there any big cuts or tears?
• Are they in reasonable condition but either common or a size that doesn't get reused much, such as knobby 26" mountain-bike tires or "Kids bike" 24" tires?

If either of these conditions holds, take the tires off and throw them away. (Unfortunately, tires cannot be recycled.)

Otherwise, if the tires are in good shape and are popular reuse candidates (e.g., 27", slick 26", 700C), then store them with the tires.

Inspect the inner tubes

• Is the valve is torn? Does the tube has a big tear or blow out? → Throw it away.
• Is the tube is flat? Is there only one or two holes? → Put the tube in the "Tubes to be patched" basket so it can be checked and patched.
• Is the tube good? → Let out as much air as possible, wrap up the tube and put it in the appropriate basket. (Baskets are marked by size.)

Inspect the freewheel or cassette.

Do we want to have explicit instructions here about how to remove freewheels and cassettes?

• Remove the cassette or freewheel.
  • If you have not done this before, ask a mechanic for help. Removing these is not hard but requires some special tools that can be stripped if not used properly.
  • Be sure that all of the spacers, all of the cogs and the lock ring on a cassette are zip-tied together
• Is it obviously worn out or broken? → Recycle it.
  • The most common signs of a worn-out cassette or freewheel are gear teeth that have become worn down on their rear edges, so that they don't look symmetric anymore, and widespread rust.
• Otherwise, put it in the freewheel-and-cassette bin with its cousins.

Inspect each hub

• Is the axle broken?
• Are any lock nuts missing?
• Does the axle feel wobbly or loose in the hub?
• Does the axle feel gritty when you turn it (or when you hold it and spin the wheel)?
• Is the axle missing entirely?

If "yes" to any of these, then the hub may need some major work before it can be reused. This work may be worth it if there's a prayer of finding the parts and if the wheel is otherwise in good shape (see next paragraph). If you need help evaluating this, ask. If the hub is in decent shape, move on to consider the rest of the wheel.

What if the hub is NOT in decent shape?  Do we want them to cut it out of a rim after
inspecting it and putting it in the hub bin?

Inspect each wheel

The easiest way to do this is to clamp them in a truing stand.

• Are they relatively straight?
• Are all of the spokes present?
• Are the nipples in good shape (i.e., not stripped or excessively corroded)?

If you've made it this far, then the wheel is probably good. Tape a piece of card stock of the right color for its size (there is a chart on the wall below the hanging wheels) and then hang it with wheels of the same size. Often the rim of the wheel is pretty bent or is missing a spoke or two. Determining how fixable a bent wheel is can be hard. If you have any doubts, ask. If the wheel is badly bent, corroded or otherwise broken, recycle it.

Here again, what if the rim is shot but the hub is good? Do we want them to separate 
them and recycle the rim while keeping the hub?

If the wheels are in really good shape, match, and have matching tires, you may consider zip-tying them together and putting them on the rack for reuse. This happens rarely.

Chain

• Remove the chain with a chain tool.
  • Please avoid bending or breaking the push-pin on the tool; if you have any doubt about how to use a chain tool, please ask.
• Is the chain very rusty? → Recycle it.
• Measure the chain with a chain gauge or ruler. Hold the ruler where an inch mark lies in the center of one of the chain's pins. Then measure twelve inches down the chain. Ideally, that mark twelve inches away should lie in the center of another of the chain's pins. If you are within 1/16" of the center of a pin, the chain could still be reused. Put it in the chain bin in the digging room.
• If the chain is stretched to where you are more than 1/16" off, recycle it.

Derailers

With the cables, housing and chain removed, the front and rear derailer should be easy to remove. The most important thing to observe while removing a derailer is that the anchor bolts that hold the cables in place and any hardware that mounts the derailer to the frame should be tightly fastened to the derailer so that these parts are not lost while the derailer tumbles around in the storage bin.

Brakes

There are several popular styles of brakes on bicycles. We address each in turn. As with derailers, the most important thing to observe while removing a brake is that the anchor bolts that hold the cables in place and any hardware that mounts the brake to the frame should be tightly fastened to the brake so that these parts are not lost while the brakes tumble around in the storage bin.

As a general issue, when someone removes brakes, do we want them to remove brake SHOES?

Side Pull Brakes

These have a long bolt that runs through the fork (in front) or a mounting bar between the seat stays (in back). If you have already removed the cables, housing and wheels then removing the brakes is simple. Unscrew the "inside" nuts, i.e., those on the "back" of the brake bolt. Slide the brake off of the bike and thread the inside nuts back onto the brake. Zip-tie the two brakes together and put them in the bin.

Center Pull Brakes

Like side pull brakes, these have a long bolt that runs through the fork (in front) or a mounting bar between the seat stays (in back). Unlike side pull brakes, these have a "yoke cable" that runs atop between the two arms of the brakes and that is held by a triangular metal "yoke" to which the main brake cable is attached. This yoke and cable need to stay with the brake! Once you have the brake removed, firmly attach them to the body of the brake with electrical tape.

If you have already removed the cables, housing and wheels then removing the brakes is simple. Unscrew the "inside" nuts, i.e., those on the "back" of the brake bolt. Slide the brake off of the bike and thread the inside nuts back onto the brake. Attach any loose parts to the brakes with electrical tape, zip-tie the two brakes together and put them in the bin.

Cantilever Brakes

These are composed of two angled arms that are attached to bosses on the tines of the fork (in front) or on the seat stays (in back). The two arms are joined by a "yoke cable," an upside-down V through one arm of which the primary brake cable runs. This yoke cable needs to stay with the brake! Once you have the brake removed, firmly attach the yoke cable to the body of the brake with electrical tape.

If you have already removed the cables, housing and wheels then removing the brakes is simple. Unscrew the pivot bolts holding the brake arms onto the frame bosses and then slide the arms off. Note that the bosses are threaded inside. This means that, once the brake arm is off the frame, there will be no threading to hold that pivot bolt in its hole, or to hold the spring on the other side in place. The easiest way to keep these together is to wrap the bottom of each brake arm, and its bits, in electrical tape.

Because they use separate arms, a complete front-and-rear set of cantilever brakes will have four pieces (plus the yoke cables). Zip-tie all four pieces of the brakes together and put them in the bin.

V-Brakes

Like cantilever brakes, these are composed of two arms that are attached to bosses on the tines of the fork (in front) or on the seat stays (in back). Unlike cantilever brakes, the V-brake arms are joined by an accordion rubber sleeve through which the main brake cable runs.

If you have already removed the cables, housing and wheels then removing the brakes is simple. Unscrew the pivot bolts holding the brake arms onto the frame bosses and then slide the arms off. Note that the bosses are threaded inside. This means that, once the brake arm is off the frame, there will be no threading to hold that pivot bolt in its hole, or to hold the spring on the other side in place. The easiest way to keep these together is to wrap the bottom of each brake arm, and its bits, in electrical tape.

Because they use separate arms, a complete front-and-rear set of V-brakes will have four pieces. Zip-tie all four pieces of the brakes together and put them in the bin.

Pedals

Pedals are threaded into the ends of the cranks. The space in which to fit a wrench is narrow, so a specialized pedal wrench exists. Each workstation has one. A pedal wrench and a cone wrench are not the same thing! Cone wrenches, which are thinner and have smaller handles, will fit a pedal bolt, but they are not strong enough to loosen stuck-on pedals without breaking. We have seen members snap cone wrenches in half by improperly using them for this task. Use the right tool!

Pedals simply need to be unscrewed. Note though that the left-hand pedal (the one that's not on the drive side of the bike) is reverse threaded. You will need to turn the wrench to the right to loosen that pedal.

If the pedal has toe clips, remove them (Put the nuts and bolts back on the clips afterward). Zip-tie together the clips and put them in the appropriate storage bin. Zip-tie together the pedals and put them in the appropriate storage bin.

Crank Set

The two main varieties of cranks are cottered and cotterless. Most donated bikes have cotterless cranks.

Cottered cranks

These cranks have a visible pin stuck sideways through the crank where it connects to the spindle that runs through the bottom bracket. These should be removed with the cotter-pin press, which looks like a heavy-duty, modified C-clamp (It lives in the red drawers beneath the main tool cabinet).

• Remove the threaded nuts from the cotter pins. Once removed, you will see that one end of the cotter pin is threaded and the other is smooth.
• Apply force with the press on the threaded end of the pin.
• Once the cotter pins have been removed, the cranks can be slid off of the spindle.
• Zip-tie the cranks together and put them in the appropriate bin.

Cotterless cranks

These are the newer technology and are easier to work with. Such cranks are removed with a crank puller; each workstation has one.

• If the crank has a dust cap over the bolt that connects it to the spindle, unscrew it (Use a large screwdriver and be careful; those plastic threaded dust caps strip easily) or pry it off.
• Remove the nut or bolt that holds the crank tight against the spindle. If the bottom bracket has a hollow spindle, this will be a hex-head bolt; if it has a solid spindle, it will be a hex nut. In either case, you can normally remove it with a 14mm ratchet.
• Wipe the threads inside the crank as clean as you can.
• The crank puller has a cylindrical drum into which the handle screws. Unscrew the handle from the drum and thread the drum into the end of the crank. Take your time and make sure that you have not cross-threaded the drum; it is easy to do this and then strip the crank's threads.
• Screw the handle into the drum. As you tighten it, you will force the crank off of the tapered end of the spindle. You will sense this as increasing, then suddenly decreasing resistance to your tightening. Once the crank is forced loose, it can be slid off.
• Thread the nut or bolt back onto the bottom-bracket spindle so that it doesn't get lost.
• Zip-tie the cranks together and put them in the appropriate bin.

Someone who has worked on Octalink bottom brackets should write up what differs
about that process.

Further Information

A Note on Parts and components

Bikes are made of components. Components are made of parts. A component that is missing some parts is not useful until you dig up the missing parts. In order for the component to work, the parts must be compatible. In some cases, achieving compatibility is not a big deal. For example, many many brakes use the same cable anchors, and those cable anchors can be readily found in the shop. When compatible parts are not readily available, or when it's not obvious which parts are compatible, you're stuck substituting and experimenting. We have seen some pretty extraordinarily successful substitutions, and we have seen some pretty big disasters. In fact, a whole book could be written on this topic. Our goal here is to minimize the need for substitution and experiment by ensuring that the components that we strip off bikes remain complete. This results in bikes that work better and are easier for members to build.