Thanks much Ryan! Just this week I started expanding our one page class topic sheet into an instructor crib sheet. With a bit of triva for conversation. 1st rough draft, LOTS missing and the citations need to be tightened up.
Ron
Overview
Rider/owner bike maintenance generally involves *inspection*, *adjustment*, and *lubrication*. Sometimes cleaning and lubrication must precede adjustment.
- Major Bike Parts 1.1. Groupset
Gruppo; from Italian for "group" (often misspelled grouppo) is a bicycle component manufacturer's organized collection of mechanical parts.
2 gear levers or shifters and
2 brake levers or
2 integrated brake levers/shifters
2 brakes, front and rear
2 derailleurs, front and rear
1 bottom bracket
1 crankset
1 chain
1 cogset, freewheel or cassette 1.2. Everything else
Frame
Forks
Handlebar stem
Seat post
Seat
Wheels (hubs, spokes, rim)
Tires 2. Tubes & Tires 2.1. Tubes
Show one of each 2.1.1. Schrader - Larger and have springs that hold the valve shut. Will lose some air when air-chuck is removed. 2.1.2. Presta - Smaller. Air pressure holds the valve shut. Adapter used for a Schrader air chuck. 2.2. Tires 2.2.1. Removing Tires (Tool: Tire Lever) 2.2.2. Checking Tubes (Tool: Bucket of Water) 2.2.3. Puncture Repair (Tool: Patch Kit) 2.2.4. Re-inflation (Tool: Bicycle Pump) 3. Groupset Inspection, Lubrication & Adjustments 3.1. Bowden cables and housings
Date from late 19th century, first used by Raleigh Bicycles in England. 3.1.1. Barrel adjuster for adjusting the cable tension using an inline hollow bolt. Lengthens or shortens the cable housing relative to a fixed anchor point (brakes or derailleur). Lengthening the housing (turning the barrel adjuster out) tightens the cable; shortening the housing (turning the barrel adjuster in) loosens the cable. Start cable end adjustments with barrel all the way in. 3.1.2. Use spray dry-lubricant if available or else Tri-Flow because of Teflon 3.1.3. Cables may have to be removed from the anchor point (brake or derailleur) to get enough cable slack to apply lubricants. 3.1.4. Rubber tori, called donuts, can be threaded onto a bare run of the inner cable to prevent it from striking the bicycle frame causing rattles or abrasion (Rarely replaced). 3.2. Brakes & Brake Maintenance 3.2.1. Common Types 3.2.1.1. Rim brakes (Wikipedia citation needed) · Rod-actuated brakes · Caliper - The caliper brake is a class of cable-actuated brake in which the brake mounts to a single point above the wheel, theoretically allowing the arms to auto-center on the rim. · Rarely found on modern mountain bikes. But they are almost ubiquitous on road bikes, particularly the dual-pivot side-pull caliper brake. · Side-pull caliper brakes Single pivot side-pull caliper brake. Single-pivot side-pull caliper brakes consist of two curved arms that cross at a pivot above the wheel and hold the brake pads on opposite sides of the rim. These arms have extensions on one side, one attached to the cable, the other to the cable housing. When the brake lever is squeezed, the arms move together and the brake pads squeeze the rim. Dual-pivot caliper brake. Dual-pivot side-pull caliper brakes are used on most modern racing bicycles. One arm pivots at the center, like a side-pull; and the other pivots at the side, like a center-pull. The cable housing attaches like that of a side-pull brake. · Centre-pull caliper brakes Centre-pull calliper brakes have symmetrical arms and as such center more effectively. The cable housing attaches to a fixed cable stop attached to the frame, and the inner cable bolts to a sliding piece (called a "braking delta" or "braking triangle") or a small pulley, over which runs a straddle cable connecting the two brake arms. Tension on the cable is evenly distributed to the two arms, preventing the brake from taking a "set" to one side or the other. · U-brakes U-brakes (also known by the trademarked term "990-style") are essentially the same design as the center-pull caliper brake. The difference is that the two arm pivots attach directly to the frame or fork while those of the center-pull caliper brake attach to an integral bridge frame that mounts to the frame or fork by a single bolt. · Cantilever The brake shoe is mounted above the pivot and is pressed against the rim as the two arms are drawn together. In the first-class lever design, the arm pivots above the rim. The brake shoe is mounted below the pivot and is pressed against the rim as the two arms are forced apart. Low profile 'traditional' cantilever brake. The traditional cantilever brake, or commonly cantilever brake, pre-dates the direct-pull brake. It is a center-pull cantilever design with an outwardly-angled arm protruding on each side, a cable stop on the frame or fork to terminate the cable housing, and a straddle cable between the arms similar to center-pull caliper brakes. The cable from the brake lever pulls upwards on the straddle cable, causing the brake arms to rotate up and inward thus squeezing the rim between the brake pads. · V-brakes Linear-pull brakes or direct-pull brakes, commonly referred to by Shimano's trademark V-brakes, are a side-pull version of cantilever brakes and mount on the same frame bosses. However, the arms are longer, with the cable housing attached to one arm and the cable to the other. As the cable pulls against the housing the arms are drawn together. Because the housing enters from vertically above one arm yet force must be transmitted laterally between arms, the flexible housing is extended by a rigid tube with a 90° bend known as the "noodle". The noodle seats in a stirrup attached to the arm. A flexible bellows often covers the exposed cable. Because of the higher mechanical advantage of V-brakes, they require brake levers with longer cable travel than levers intended for other types of brakes. Cheap or poorly-specified V-brakes can suffer from a sudden failure when the noodle end pulls through the metal stirrup, leaving that wheel with no braking power whatsoever. Although the noodle can be regarded as a service item and changed regularly, the hole in the stirrup may enlarge through wear. The stirrup cannot normally be replaced, so good quality V-brakes use a hard and tough steel for the stirrup.[14] 3.2.1.2. Disk 3.2.1.3. Drum brakes 3.2.1.4. Coaster brakes 3.2.1.5. First invented in 1898, the coaster brake, also known as a back pedal brake or foot brake (or torpedo in some countries), is a type of drum brake integrated into hubs with an internal freewheel. Freewheeling functions as with other systems, but when back pedaled, the brake engages after a fraction of a revolution. The coaster brake can be found in both single-speed and internally geared hubs. 3.2.1.6. When such a hub is pedaled forwards, the sprocket drives a screw which forces a clutch to move along the axle, driving the hub shell or gear assembly. When pedaling is reversed, the screw drives the clutch in the opposite direction, forcing it either between two brake pads and pressing them against the shell, or into a split collar and expanding it against the shell.[1]https://mail.google.com/mail/u/0/html/compose/static_files/blank_quirks.html#_ftn1 3.2.2. Evaluating Wear
Pad wear groove. 3.2.3. Alignment & Adjustment (Tool: Third-hand Tool, Fourth-hand Tool) 3.2.3.1. Pads 3.3. Chains & Chain Maintenance 3.3.1. Evaluating Wear (Tool: Chain Wear Indicator) If worn don’t bother cleaning, replace and check chain-ring and cogs for wear.
3.3.2. Check for tight chain links. They may affect shifting. 3.3.3. Cleaning & Lubricating (Tool: Chain Cleaner, Lubricant) 3.3.4. Removing & Replacing (Tool: Chain Breaker) 4. Shifters & Dérailleurs
Shifters and derailleurs and part of a system that relies on cables, springs, alignment, and a maintained chain. Best if everything is clean and lubricated.
Troubleshooting:
Some information copyright of www.bikebooboos.com.
Check the easy things 1st. While spinning the chain-ring check for proper shifting. Make sure cables are free and when the derailleur is at the highest gear setting (smallest cog) the cable is loose enough to deflect but not so loose that moving the shifter doesn’t do anything. Adjust if necessary and
Before adjusting the derailleur screw settings, consider other potential sources of your poor shifting problem.
- If the rear shifter works properly when using the large chain ring but
not the small chain ring, or vice-versa, then the rear derailleur hanger might be bent.
- If the shifting skips when you apply pressure, check that your chain
and cassette are not worn.
- If the shifting skips every third or fourth pedal revolution, check for
a tight chain link.
- If the shifting skips when you go over a bump, and you are riding a
full suspension bike, check that your cable housing is long enough. It may be stretching as the suspension flexes, causing the gears to ghost shift at that time.
- Dirty, rusty, kinked or damaged cables and cable housing will also make
shifting a problem. Index shifting is very sensitive to excessive friction in the cable.
Having ruled out these sources of concern, follow this procedure to adjust your shifting.
First check the derailleur’s range of motion.
The high and low gear limit screws determine how far the derailleur can shift to the left and right. Too far to the left, and your chain ends up in the spokes. Too far to the right, and it ends up grinding away your dropout.
Usually the screws are labeled H and L, but if not, high is typically on top, low is on the bottom. I once had a derailleur labeled I and J … until I turned it clockwise 90 degrees!
To check the leftmost range of motion, put the bike into the smallest front chain ring and the lowest rear gear (largest cog). Looking from behind the bike, the pulley wheels should be directly beneath the largest rear cog.
Now move to the largest front chain ring, and the highest rear gear (smallest cog). Looking from behind, the pulley wheels should line up just slightly to the right of the smallest rear cog.
If the chain isn’t on the bike at this point, just push the derailleur as far as it will go in each direction to perform this check.
If the pulley wheels don’t line up, use the appropriate gear limit screw (H = High = highest rear gear = smallest cog) to move the derailleur. You will see the pulley wheels move when you turn the screw. For both adjustments, counterclockwise turns typically let the pulley move further; clockwise turns limit its movement.
Two screws to move the derailleur.
H = High = highest rear gear = smallest cog
L = Low = Lowest rear gear = biggest cog)
You will see the pulley wheels move when you turn the screw. For both adjustments, counterclockwise turns typically let the pulley move further; clockwise turns limit its movement.
4.1. Types, Components 4.2. Alignment & Adjustment 4.3. Slack cable 4.4. Low end 4.5. High end 5. Gears/Cogs/Sprockets/Freewheels/Cassettes/Chain-rings 6. The Variables of Bike Fit 6.1. Frame Size, Crank Length 6.2. Stem Length & Height 6.3. Saddle & Seat post Height 6.4. Handlebars 7. Bonus: Basics of Wheel Truing
Right hand threads, nipple is in from back so thread acts reversed.
[1]https://mail.google.com/mail/u/0/html/compose/static_files/blank_quirks.html#_ftnref1 http://en.wikipedia.org/wiki/Bicycle_brake#Types_of_rim_brakes accessed May 24, 2011
On Thu, May 26, 2011 at 1:26 PM, ryanguzy@gmail.com wrote:
We've got step by step handouts for our maintenance classes. I'll send links to the google docs later today or tonight. These could also go up on the Wiki, I haven't looked into it yet though.
Ryan Guzy Bike Saviours Collective Tempe, AZ
On , John Barrett Jonny@goodlifebikes.ca wrote:
Hi,
Does anyone have documents for step-by-step individual mechanical
tasks (IE rear derailleur adjustment). We want to make individual
instruction sheets to have available in the shop so that it's really
simple for folks to learn on their own.
I realize this sort of thing is widely available through many books
and the Internet, but it would be great if there's an already
formatted doc available.
Thanks!
--
John Barrett
The Good Life Community Bicycle Shop / Two Wheel View - Calgary / The
Organic Saskatoon & Iron Orchard
jonny@goodlifebikes.ca
403.619.2648
Thethinktank mailing list
Thethinktank@lists.bikecollectives.org
To unsubscribe, send a blank email to
TheThinkTank-leave@bikecollectives.org
To manage your subscription, plase visit:
http://lists.bikecollectives.org/listinfo.cgi/thethinktank-bikecollectives.o...
Thethinktank mailing list Thethinktank@lists.bikecollectives.org To unsubscribe, send a blank email to TheThinkTank-leave@bikecollectives.org To manage your subscription, plase visit:
http://lists.bikecollectives.org/listinfo.cgi/thethinktank-bikecollectives.o...