(It makes the bicycle go vroom!)

Bottom brackets are an essential part of the bike. Without them you would not be able to pedal. It is sandwiched in between the crank arms in the part of the bicycle called the bottom bracket cage. The bottom bracket is merely a spindle that rides on two sets of bearings and races, one on each side. The spindle sticks out on both sides and connects to the crank arms and then the pedals. There are three basic types: sealed cartridge, adjustable, one-piece.

• • A sealed cartridge means the bearings and axel are encased and only one cup is loose. This protects the bearings and is much more durable than an adjustable or one piece bottom bracket.
  • An adjustable bottom bracket consists of all the pieces separate. This style is very serviceable and is what is most commonly found in the Green Bike Shop.
  • A one piece bottom bracket is simply one piece that is the axel and both crank arms. This can be slightly serviceable as long as the races on the axel are not worn. If they are, the entire piece must be replaced.

Problems that arise with the bottom bracket are few; most of the time it is a worn or loose bottom bracket. A worn bottom bracket usually means the bearings are becoming crushed and/or the races are wearing in. This leads to further deterioration until the bearings are cracked and the bottom bracket seizes. A loose bottom bracket could lead to crushed bearings and/or the crank arms to come off.

Assessing whether or not the bottom bracket has one of these problems is simple. Take the chain off the crank set and spin the crank arms. If you feel a grinding vibration or hear grinding coming from within the bike, this probably means the bottom bracket is worn. A loose bottom bracket can be easily detected by grabbing both crank arms near the pedal and torque both arms towards and away from the bicycle. If you feel play when doing this it could be that either the bottom bracket is loose or the crank set itself is loose.

In order to service the bottom bracket:

• • Place a rag to the side. This is where you will put the parts you take off the bike in order so as to help with reinstallation.
  • Take off both crank arms by loosening the crank bolts and removing the crank arms with a crank puller.
  • If the bottom bracket is loose, tighten the loose cup(s)/lock ring one eighth of an inch at a time. After each eighth check to make sure the spindle is still loose.
  • If the bottom bracket is worn, remove the loose cup/lock ring and carefully place the bearings aside.
    • Next remove the axel.
    • If the bottom bracket is a sealed cartridge bottom bracket by removing the fixed cup the bottom bracket should come out.
    • Finally remove the opposite cup and bearings.
    • If the bottom bracket is a sealed cartridge it cannot be serviced and must, sadly, be thrown away.
    • If it is an adjustable style, clean and examine the axel, both cups, and the bearings. If any is worn replace it.
    • Reinstall all parts opposite the way they were taken out; making sure to grease both sides of the bottom bracket.

Brakes are a very simply mechanism yet there can be so much that goes wrong. How can we figure out what is wrong? We must use our critical thinking skills and understanding of how a brake works to test and try until we figure out what is wrong. With our basic knowledge we can apply these steps to almost any brake and be able to figure out some way to fix it.

A brake works when you pull the cable. The cable is contacted to a pair of swing arms attached to two springs (the springs are what allow the brake to return to its starting position). These arms have pads on them that then contact the rim and create friction. This friction is what slows, or brakes, the wheel.

Assessment of a brake is very simple. Some might even say fun. Spin the wheel of the brake in question and pull the lever. Do these repeated times. Feel for stickyness in the brake, if the caliper and/or the lever return to their starting position rapidly and cleanly. Look at the brake pads. Are they contacting the rim when you squeeze the lever? Are they contacting at the same time? Do the brakes squeak? When you are riding the bike do the brakes seem inefficient like they are not doing their job? Do the brakes contact the rim when the lever is halfway from the starting position to the bar?

Once these questions have been answered you can now take the necessary steps to remedy the problem.

If the brakes are sticky meaning they do not return to their original position here are some possible solutions:

• Check the cable and housing if they seem dry or dirty apply some lube and rub the cable off. Make sure to apply a few extra drops where the cable enters and exits the housing.
• If the cable looks rusty it probably needs to be replaced.
• Sometimes the housing pops off of the housing holder on the frame. Simply put the housing back through the holder.
• Check the brake itself. One of the springs could have come loose and/or is not working. This will require you to either put the spring back on or replace the spring/caliper.
• Check to see if there is a lot of gunk around the brake. Sometimes a good old cleaning can do miracles

If the pads are not contacting the rim here are some ways you can fix them:

• Loosen the screw holding the pads in place and align them with the rim. This might take a few tries. Make sure not only is the pad horizontally level with the rim but depth wise too.
• Are the pads dry? Sometimes dry pads could lead to poor braking and squeaky braking. Attempting to sand the pad could rough up the surface but if this does not work, replace the pad.
• Check to see if the pads are contacting the rim at about the same time. If this is not happening adjust the tension spring until proper contact time is achieved.

If the brakes do not seem very efficient check some of these for reasons why:

• The brakes exhibit the above problems.
• Sometimes the type of pad makes a world of difference. A new pad for the purpose does miracles when it comes to braking efficiency.
• Some brakes just do not work. Make sure to notify the owner of the bicycle of their possibly problematic equipment.

If the brakes do not contact the rim when the lever is halfway from the starting position to the bar then look at these:

· There might not be enough cable tension. Make sure the barrel adjuster is tightened all the way. Loosen the cable bolt on the brake. Take in about a half centimeter of cable. Retighten and check brake. Continue until desired effect is reached. If this does not work. The lever and brake might be incompatible.

Sometimes even the most basic problems have strenuous solutions. Do not be afraid to experiment and try different solutions. Once finished always ask a more experienced work hand whether the job has been done completely and properly. Above all have confidence in your assessment.

Stolen 8 bikes and 1 seat

Of those 8:
1 was not locked up
1 was locked by the wheel only.
4 were locked by the frame only.
2 were locked by the frame and wheel.

Where:
2 were locked by the freshman dorms.
2 were locked by Holden.
2 were locked by Mead.
2 were locked off of Pitzer’s campus.

When:
Most were locked overnight
One was locked in one place for an extended period of time.

Type of Bike:
6 were mountain bikes
2 were road bikes

Lock Used:
7 were locked with a cable lock
1 was locked with a U-Lock

The Pitzer Green Bicycle Program recommends the following for personal bicycle safety:
We can for certain say that u-locks provide much more security than cable locks. Aside from this, from a strictly data perspective, more data is needed to make official statements. However, we also recommend not leaving your bike locked to the same rack for an extended period of time. Do not lock the bike through solely the wheel.  Also, please take a moment to register your bike at the national bike registry http://www.nationalbikeregistry.com/.

Make sure to copy your bike’s serial number and keep it in a safe place. When the bicycle is stolen be sure to file a police report as soon as it happens.

If you witness any suspicious action taking place near a bike such as the cutting of a lock via a saw or cutters please report it to camp sec immediately. IT COULD BE YOUR BIKE! DO NOT CONFRONT THE PERPATRATOR.

for the safety of bicycles everywhere,
The GBP Crew

Here is the tentative schedule of what is to come with classes.

Green Bicycle Program Classes

I. Your Bike

a. The parts of a bike.

b. How they work

c. Upkeep

II. Flats

III. Brakes

a. Levers

b. Cables

c. Calipers

i. Pads

IV. Deraillures

a. Shifter Levers

b. Cables

c. Front

d. Rear

V. Headsets

a. Threaded

b. Non-threaded

VI. Bottom Brackets

a. Cranksets

VII. Wheels

a. Truing a wheel

b. Hub bearings

c. Cassette/Freewheels

Please send emails regarding class attendance to edumont@students.pitzer.edu

Here is the lesson plan from last class:

b. How they work.

The frame is the skeleton of the bicycle. All parts of the bike connect to the frame. There are many different types of frames some of the more popular frame types are a road frame, mountain bike frame, and BMX frame. From those three categories there are a multitude of sub categories (i.e. road racing frame, full suspension mountain, trials, dirt jumping, etc.)

.The fork is typically associated as part of the frame. This is the part of the bike that holds the front wheel. The two arms are the part that the wheel clamps to. The tube that runs through the frame is the steerer tube because it is what the stem and then handlebar clamp to in order to steer the bike. The fork is able to rotate within the frame thanks to the bearings that rest within the frame.

The wheels are the next most important part. Without them the bike would not be able to move! The wheels are really a compilation of many other parts such as the rim, spokes, nipples, hub, tire, and tube.

The hub of the wheel can be broken down even more to the house, bearings, races, and axle. There are more parts for the rear hub because this is where the majority of the gears are located. The gears rest on an extension of the hub. These will be explained later on.

The chain is what enables the rider of the bike to transfer their force to the gears of the bike in order to turn the wheel and thus move the bicycle! It comes in varying sizes for different bicycles the two most common sizes are 3/32 for a normal road/mountain bike and 1 1/8 for BMX/cruiser/singlespeed bike.

The bottom bracket is what allows you to turn your pedals. It is a set of bearings on each side of the frame that rests on races with an axel that runs through the frame. The axel is connected to the crank arms. The crank arms are what the pedals connect to. Both crank arms and the chain rings are called the crank set.

There are two basic types of crank sets, a one piece and a three piece. The number refers to the pieces involved in the crank set. A one piece is just one continuous piece of medal that acts as the crank arms and axel. A three piece has two individual crank arms and an axel to make a total of three pieces, duh!

The cassette is where the majority of the gears are located. The smaller the individual cog (gear) is the harder it is to pedal and visa versa. There are different types of cassettes and many different sizes for different uses (road, mountain, etc.) Two basic types are freewheel cassettes and cog cassettes. Freewheel cassettes thread on to the hub of the rear wheel. All of the gears on a freewheel are attached to each other. A cog cassette is made up of up to 10 individual cogs that are stacked onto the hub of the rear wheel and held in place by a lock ring.

The derraillures move the chain from one gear to the next. There are two basic types of derraillures on a bicycle; the front and the rear. The front derraillure moves the chain from one chainring on the crankset to another. The rear derraillure moves the chain from one cog to another on the cassette. They are controlled by cables which are connected to shifters on the handlebars. Another type of derraillure and gear setup is the internal gears which are encased in the rear hub of the read wheel. These are also controlled by a shifter but are a little bit more complicated to work with.

The brakes are located in the front or the rear of the bike. Sometimes bikes either have a front, rear, or both brakes. Most cruiser style bikes have one rear brake called a coaster brake. Brakes work by rubbing a pad against a part of the wheel. The friction causes the wheel to slow down and thus you as well! Most brakes contact the rim of the wheel. Coaster brakes work the same way but the brake is located in the hub of the rear wheel. Disc brakes work the same way but instead of being in the hub or on the rim they rub against a separate disc that is located by the hub.

The cables are the veins of the bicycle. Without them one would not be able to shift gears or control the brakes. There are normally four cables on a bike; two for the front brake and derraillure and two for the back brake and derraillure. They are encased in parts by a larger black tube called the housing. The housing protects the cable from rubbing against the frame and unraveling or fraying.

The handlebar is the command center of the bicycle. It is not only where you rest your hands and steer but is also where the levers for the brakes and shifters are along with such things as bar ends. The levers for the brake and shifters work by tightening or loosening the cable of either the brakes or deraillures. This moves the brakes or deraillures to another gear or to contact the rim or braking surface. There are different types of handlebars each has a different use. Drop bars are commonly found on road bikes whereas flat bars can be found on mountain bikes.

The stem is what connects the handlebars to the steerer tube of the fork. These come in different types, lengths, and angles. The quill stem has a wedge that fits into the steere tube and is tightened by adjusting a bolt on top of the stem. A clamp stem works by simply clamping around the steerer tube with up to 4 bolts.

The seat is the most comfortable part of the bike and without it you would be hard pressed to ride your bike for a long time. There are hundreds of seats each a little different and better in their own way. Most of the time seats are based on personal preference and there is no right seat for a specific bike. The seat consists of the seat itself, the guts, and the seat post. The guts of the seat are the bolts under the seat that clamp it to the seat post. The post allows the seat to be clamped to the bike by the clamp which wraps around the frame by the seat tube.

a. Upkeep

Bicycle upkeep is very simple and could help to increase the life of your bicycle and all its parts. So show your bike some love and follow these simple steps.

1) Check your tires! The easiest way to avoid flats and trouble with your bike is to make sure your tires are always properly inflated. If you don’t know how to pump up your tires, how much air should be in them, or if they need to be replaced bring them into a bike shop and say, “HELP ME!!!!!!!”

2) Be sure to lube your chain at least once every two weeks. Not a lot just a few drops here and there will do. This keeps the drivetrain (the chain, cassette, draillures, and chainrings) well lubricated and decreases the wear and tear over time.

3) Lube your cables once a month. This helps the cable move in and out of the housing as you shift or brake. It also protects the cable from weather and fatigue.

4) If you hear any noises that you didn’t hear before on your bike or think something is wrong with your bicycle, BRING IT INTO A SHOP. A lot of times people begin to hear funky noises or think something is wrong and continue to ride on their bicycle. This is not good. Doing this for too long you can make a problem that could have been fixed by tightening a bolt to something worse like replacing a part or possibly buying a new bike. It can also be dangerous, especially if you do not know exactly is wrong.

II. Flats

Flat tires are the most common problem encountered with bicycles. These could be caused by a thorn, something slicing the tube, or just an old tube that has failed. Here is how to replace a tube.

1) If the wheel is not off the bicycles. Detach the wheel by either loosening the quick releases or axel bolts and releasing the brakes.

2) Once the wheel is off the bike grab a pair of tire levers. And work one side of the tire off the rim by inserting the hooked end of the tire lever in between the tire and rim. Pull down on the lever to lift the tire up off the rim and repeat until one side of the tire is off the rim.

3) Once one side of the tire is off the rim reach into the tire and pull the tube out of the tire.

4) Inflate the tube a little and submerge it into water, looking for air bubbles.

5) Once the hole is found decide whether it is patchable or not. A patchable hole should be no bigger than a pin hole in order for the patch to properly do its job. Large slices more than half a centimeter in length cannot be efficiently patched and will lead to more troubles. If it is not patchable use a new tube.

6) To patch a tube locate the hole, dry the surface if you used water to find the hole, rough up the surface around the hole with fine sand paper. Make sure the surface you rough up is larger than the area of the patch. Now apply a liberal amount of glue to an area also larger than the patch and let it dry for about 2 minutes. Once the glue has started to dry apply the patch making sure to message it for about another 2 minutes to ensure there are no air bubbles in between the patch and tube. Let it sit for a final 2 minutes, inflate, and test under water.

7) Before reinserting the tube check the tire by rubbing your fingers along the inside of the tire to feel for thorns. Once the thorn is found remove it with needle nose pliers. There might not be a thorn or needle so do not worry if you cannot find one. Also examine the outside of the tire for cuts or holes in the tire. If there are none then reinsert the tube.

8) To reinsert the tube into the tire, inflate the tube until it holds its shape, insert the stem first into the hole in the rim, making sure the stem is as straight as possible.

9) Continue to feed the tube into the tire starting at the stem and working around the tire until you reach the stem again.

10) Once you have returned to the stem, check to make sure the stem is still straight. If it is not, straighten it. If it is, start to place the tire back onto the rim first with your hands. Start at the stem and work around the rim until you get back to the stem.

11) There might come a point where you can no longer use your hands to place the tire on the rim. Use a tire lever in the opposite action that you used to take the tire off to put the tire back on.

12) Once the tire is back onto the rim and before inflating it, pinch the tire and move it back and forth. Continue to do this around the entire tire. This helps to keep the tube contained within the tire and helps to prevent against pinch flats when inflating the tire.

13) Now that you have done all the preceding steps. Inflate the tire a little bit at a time, checking to make sure the tire is not popping off the tire. Continue to do this little by little until you have reached the proper tire pressure for the tire you are working with. This information can be found on the side of the tire. If you cannot find the information follow these basic rules of thumb ( Mountain bike tires 45-65 PSI, Road 100-120 PSI, BMX 35-45 PSI, Cruiser 45-65 PSI, Hybrid or Larger Road 85-95 PSI).

http://midnightridazz.com/viewProfile.php?userId=178
http://www.bikeboom.com/
http://www.lafixed.com/ (this one you need to sign up to view & here you can find the thread for the Tues. night Juggernauts (Claremont) ride!)
http://www.bicykillers.com/
http://gogabikeride.blogspot.com/ (this one is females only ride)
http://bikeoven.com/spokenart/

and for non-profit bike repair…. here are these two

http://www.bicyclekitchen.com/
http://bikeoven.com/

This guy Madex does a bike in~drive in movie night once a month. it takes place usually in a closed parking lot some where in downtown, and the films are projected on the wall. he all ways does a double feature, it is all ways free, all ways on a sunday, and all ways fun!

next one is on the 19th
he has a my space for those of you that do
http://profile.myspace.com/index.cfm?fuseaction=user.viewprofile&friendid=181050120

other wise i have his email… if you want to get on the list
madexmovienight@gmail.com