Guide to Stripping Bikes

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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 that people can use them to build up other bikes.

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 done out of order. 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 and is based on working from the outside inward, that is, starting from the top-most and easiest-to-remove parts and stripping off layers. 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 components removed just to get it working, as when major components are broken? → Such components, but probably not the entire bike, should be stripped.
  • Does the bike have unique components 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 components? → 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 parts and components

Bikes are made of components, like brakes; components are made of parts, like levers and bolts. A component that is missing some of its parts is useless unless and until you dig up compatible parts to replace the missing ones. 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 though, or when it is not obvious which parts are compatible, you get stuck substituting and experimenting. We have seen some pretty extraordinarily successful substitutions, and we have seen some pretty big disasters. An entertaining 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.

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

The ideal way to strip a bicycle is to work "From the outside in," starting by removing "superficial" and easily interchangeable parts like accessories and cables and working inward toward more crucial and bike-specific components like the headset and bottom bracket. This is the opposite order in which you would build a bicycle up, and therefore stopping at any point in this process if you proceed in order leaves the bike in a better position to be built back up by a member. We cover each major group of components in turn.

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.

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. Cables and housing are meant to be replaced at regular intervals. When removing cables and housing it is more important to preserve the components they connect than to keep the cables and housing intact.

Removal

  • Find the end of the cables at the brakes and derailleurs
  • Cut the inner steel cable between the anchor bolt and the housing with the cable cutters. (This should keep all anchor bolt pieces with the brake or derailleur)
    • 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.
  • Cables have molded ends that are held in place within the brake levers and shifters. Cut the cable so that about 2 inches of cable extend beyond the brake levers or shifters. (This will help the person who uses the component how the cable is removed and inserted correctly into their part)
  • 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 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.

  • 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. Put the wheel in the recycling


Inspect each wheel

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

  • If the rim is steel (magnet sticks to it) then put it in the recycling
  • Is the wheel relatively true? (no major side to side or up and down wobble)
  • 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. If the hub is a particularly nice one, consider cutting the spokes and saving 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

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. Use zip ties and/or electrical tape to keep loose parts together.

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. Use zip ties and/or electrical tape to keep loose parts together. Leave the brake pads on the brakes

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.


Handle Bars and Stem

There are two methods of connecting handlebars to stems:

  • "Pop top" stems have a face plate that is attached to the end of the stem with two bolts. Removing the handlebars from these is easy: unscrew the face plate. Once the bars are removed, screw the face plate back on so it won't get lost, and then proceed to strip the handlebars and remove the stem.
  • "Pinch bolt" stems on the other hand curl around the handlebars and are held together by one, pinch, bolt. To remove the handlebars from these, you must first strip off one side of the bars. Then unscrew the pinch bolt and slide the bars out. Remember to screw the pinch bolt back in so it won't get separated from the stem. You can then proceed to strip the rest of the handlebars and remove the stem.

Stripping handlebars

  • If the bars have tape on them, remove it. Tape can usually just be peeled off.
  • If the bars have grips on the end, remove them using a screwdriver and some WD-40 or similar lubricant. Loosen any brakes or shifters and slide them toward the center of the bar, then slide a flathead screwdriver into the top of the grip. Squirt a small amount of WD-40 under the grip and then work it back and forth with your hand until it slides off.
  • Tape normally cannot be reused; trash it. Also throw away grips unless they are in very good condition.
  • Unscrew and slide off any brake or shifter levers on the bike. Once the levers are removed, be sure to reattach their mounting nuts and bolts so that these are not separated from the components.
  • Inspect the brakes and shifters. (Ask a mechanic for advice if you are not sure about your diagnosis.) If they are reusable then zip-tie the pair together and put them in the appropriate bin. If they are damaged or worn out, trash them.
  • Store the handlebars with the others.

Removing threaded stems

  • A threaded stem has an "elbow" in it and runs from the handlebars right down into the steering tube.
  • Loosen the star nut in the elbow of the stem part way. When the head of the nut is visible, whack it with a rubber mallet. This will loosen the expander inside the steering tube. The stem should then slide up and out of the fork.

Removing threadless stems

  • A threadless stem runs from the handlebars to the top, steering tube of the fork and then wraps around it using two pinch bolts.
  • Loosen the star nut atop the stem and remove the dust cap.
  • Loosen the pinch bolts and slide the stem up and off of the steering tube.
  • As always, reattach the stem bolts so they are not separated from the stem.

Stems should be placed in the appropriate bins.

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 the Park CCW-5 crank bolt tool.
  • Remove any washers
  • Wipe the threads inside the crank as clean as you can.
  • Look at the shape where the crank arm meets the spindle - if it is square, use the blue square taper crank puller. If it is round with splines, use the black Octalink/ISIS crank puller (behind the greeter desk)
  • 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.
  • If the cranks' threads have been stripped, for example from someone trying to to use the crank puller without first removing the spindle bolts, recycle them.

Headset

The headset refers to the various rings, cups and races that hold the fork to the frame. The dimensions of bike tubing vary a lot, and so there are many sizes of headset. Headsets have many parts (at least five) that should stay together, because these parts cannot necessarily be swapped between headsets. Furthermore, the headset is integral to holding the frame and fork together.

For all of these reasons, unless we are recycling a frame, the headset should stay on the bike. These instructions are here only for those cases where we want to remove the headset before recycling a frame.

Threaded headsets

  • Pay attention to the order in which you remove pieces. At the end you will zip-tie all of these pieces together, and it's good practice to line them up in order before tying them together.
  • Use an appropriately-sized headset wrench to unscrew the lock ring on the top of the headset.
  • Remove any washers and/or spacers between the lock ring and the top race.
  • Unscrew the top race, which will also require the right size of headset wrench. Watch out for loose ball bearings here!
    • Once you have unscrewed the top race, there will be nothing holding the fork to the frame. Have a hand under the fork to support it as you remove the top race. There are also bearings at the bottom of the head tube, so carefully ease the fork out of the head tube.
  • Remove any ball bearings from the races.
  • Use a mallet and the headset cup removing tool to pop the headset cups out of the head tube.
  • Use the crown race puller to remove the crown race from the fork. (This is another very specialized tool that you should ask for help with if you have never used it before.)
  • Check all of the ball-bearing races for pitting. A visual inspection is a good place to start. Wipe the races clean of grease and grime and look for scratches or pits in the shiny area where the bearings turn. If you can, run the nib of a ball-point pen along each race; this will let you feel pits or grooves that might be hard to see. If there is any sign of non-trivial scratching or pitting in the races, then recycle them. Put away the other parts of the headset as incomplete parts in the appropriate drawer.
  • If the races are all good, stack the pieces of the headset in the order in which you removed them. Zip-tie the pieces together and place them in the appropriate bin.

Threadless headsets

Needs text.  My lack of experience with newer bikes is hurting me here: 95 percent of the headsets
that I've worked on have been threaded.  If someone with more experience with threadless can fill in
this part, that would be great.

Bottom Bracket

Bottom brackets are another component where sizing is both non-standard and difficult to gauge without the component in hand. Therefore, if we plan to keep the frame, then the bottom bracket should remain on the bike. Even if it needs overhauling, its presence allows whoever claims it either to do the overhaul or to take the necessary measurements to replace it. These instructions are only for removing the bottom bracket from a frame that we plan to recycle.

There are two main types of bottom brackets: three-piece and cartridge. We address each in turn.

Three-piece bottom brackets

These consist of a spindle (to which the cranks were connected) and two cups, with ball bearings in between them. Older cotterless-crank bottom brackets and all cottered bottom brackets are three-piece. On all such bottom brackets, the drive-side cup is known as the "fixed" cup and the other is known as the "adjustable" cup.

  • Take the spindle bolts off of the ends of the spindle.
  • Using a lock-ring wrench, loosen the lock ring on the adjustable cup.
  • Using the appropriate wrench or pin spanner, unscrew the adjustable cup. Note that there are a variety of different bottom-bracket cup designs and a variety of wrenches to match them. If you are not sure which tool to use, ask. This is not a job for a big adjustable wrench!
  • The bearings in the cup may be loose or caged. Watch for them as you pull the cup out.
  • Remove the spindle and the bearings from next to the fixed cup, if you can.
  • Using the appropriate wrench, unscrew the fixed cup. This cup is almost always reverse-threaded, which means that you will have to turn to the right to loosen it. (A small handful of French, Italian and Swiss bikes have fixed cups that are regular-threaded; this is one of the most annoying things in bike mechanics.) Many fixed cups were originally screwed on incredibly tightly and thus require a lot of force to remove. This can be hard to do with a thin-headed wrench without rocking the wrench off of the cup and possibly stripping it. We have a bottom-bracket-removal jig to hold the wrench in place; ask a mechanic if you think you might need it.
  • Recycle the bottom bearings.
  • Check all of the ball-bearing races for pitting. A visual inspection is a good place to start. Wipe the races clean of grease and grime and look for scratches or pits in the shiny area where the bearings turn. If you can, run the nib of a ball-point pen along each race; this will let you feel pits or grooves that might be hard to see. If there is any sign of non-trivial scratching or pitting in the races, then recycle them. Put away the other parts of the bottom bracket as incomplete parts in the appropriate drawer.
  • Place the cups over the ends of the spindle and thread the spindle bolts back on; these will keep the cups from sliding off the spindle while the bottom bracket is in the bin. If the bracket is from a cottered-crank bike or similar system without spindle bolts, place the cups back on the spindle and then use a zip-tie to cinch them together against the shoulders of the spindle. Place the spindle in the appropriate bin.

Cartridge bottom brackets

Cartridge bottom brackets have two pieces instead of three. One of the cups, usually the fixed one, is attached to the spindle. Additionally, the bearings themselves are sealed in a large cartridge around the spindle; hence this type of bottom bracket's name. The other cup is often plastic and care should be taken not to strip it during removal.

  • Take the spindle bolts off the ends of the spindle.
  • Using a splined bottom-bracket removal tool, unscrew the adjustable cup. Note that there are a variety of such tools, though they are more standardized than the wrenches for three-piece bottom brackets. In all cases, the tool mates with splines on the inside of the screwed-in cup. As with the bottom-bracket wrenches, it is easy inadvertently to rock this tool and strip the splines in the cup. We have a different jig for holding these tools in place; ask a mechanic if you think that you need one.
  • Still using the bottom-bracket removal tool, unscrew the fixed cup. This cup is reverse-threaded, which means that you will have to turn to the right to loosen it. Again, use the jig to hold the tool in place if you need to. The fixed cup and the spindle will come out as a single unit.
  • Inspect the bottom bracket. Cartridge bottom brackets are not meant to be overhauled; therefore, if the spindle feels particularly stiff or gritty when it is turned, then the bottom bracket should probably just be replaced. In this case, the bottom bracket goes in the metal recycling.
  • If the bottom bracket still seems to be in good shape, then slide the adjustable cup back onto its end and thread the spindle bolts back onto the ends of the spindles so that the parts won't be separated while the bracket is in the bin. Place the bottom bracket in the appropriate bin.
If someone knows their way around one-piece cranks and/or external-bearing bottom brackets,
this would be an excellent place to add that information.

Frame and Fork

At this point, you should be staring at a bare frame and fork. One or both are meant to be recycled.

(If we are keeping both of them, then we did something wrong, because the headset should still be on the bike and the frame and fork should be attached.)

  • Recycle whatever's meant to go out the door.
  • Store the fork with the other bare forks on the wall.
  • Get a plain manila tag for the frame. On it, write the date that you stripped the frame. (If the frame had a tag on it before you started stripping, just update that tag with the date and note that it was stripped then.) Also measure from the center of the bottom bracket to the top of the seat tube. This length, in inches or centimeters, is the bike's "size." Write that on the tag as well.
  • Hang the frame on the wall as an available project bike. Congratulations, you're done!