External Maintenance

Curriculum

Day 1 : Flat Repair

Bicycle Anatomy

• Frame tubes
• Components
• Brief quiz

Basic Chain Maintenance

Types of Lubricants

• Dry vs. Wet; describe, compare
• Different types of dry: teflon, parafin, silicon, plastic
• Wet on dry ok; dry on wet not ok

Lubricating vs. Cleaning

• How often, how do you know when
• Basic lubrication; keep it slightly glistening
• Light cleaning; rinse the dirt out w/ lube
• Remove, soak and scrub
• Remove all solvent before lubricating

Flat Repair

Tire/Rim Anatomy

• Bead; materials
• Rim hook
• Engagement

Types of Valves

• Identification
• Operation
• Rim compatibility; adapter gasket
• Pump compatibility

Removing Wheel

• Open brake
• Proper gear; reasons

Removing Tire

• Use of levers
• User of hands
• Stubborn tire tricks
• Avoid puncture
• Don't user metal levers

Finding the Leak

• Types of flats
• Relative orientation of tire/tube
• Finding leak; circle it
• Checking tire

Patching

• Types of patches ; glue-on, self-adhesive
• Vulcanization reaction
• Prepping tube, applying glue
• Applying patch

Re-assembly

• Installing tire
• Inflation steps; proper seating
• Installing wheel on bike

Day 2 : Gears

Chain Replacement

Chain Wear

• Indicator tool
• Stretch
• Cog wear, chain rings
• Behavior/interaction of worn parts; skipping, stiff link

Chain Anatomy

• Plates; inner, outer
• Pin; flanged ends
• "Link"; actually 2 segments
• Sizes; road, 10spd, BMX/Track

Chain Breaker

• Basic Principle; small vice
• Different sizes; road/10spd, BMX/Track
• Difference between upper and lower slots; upper spreads chain, lower compresses chain
• Don't push the pin out!
• Breaking* one step; joining* 2 steps
• How to tell when it's correct

Gears

Cable Principles

• Tension/Compression
• Barrel Adjusters; 'loosening' the adjuster means 'tightening' the cable; start in the middle

Shifting Principles

• Friction vs. Index
• Backlash and Overshift
• Indixing is in the shifter, not the deraileur
• Standards, manufacturers and inter-compatibility; GripShift

Deraileur Anatomy

• Parallelogram, cage, pulleys
• Wrap Adjust Screw; keeps jockey pulley from hitting large cog
• Limit Screws; demonstrate functionality
• Compare to front; position on seat tube

Exercise

• Shift out of smallest chain ring
• Disconnect cable, put all screws/barrel adjusters out of position
• Adjust screws first; just a bit wider than perfect to allow for overshift
• Connect cable and adjust tension
• Adjust for other chain rings

Shifting Technique (time permitting)

• Cross gearing
• Reduce load; timing w/in pedal stroke
• Shift when decelerating
• Shift before hills

Day 3 : Brakes

Cables/Housing Types

• Cable sizes, ends
• Housing sizes
• Housing construction, brake vs. deraileur
• Housing failure modes; why shifter is unsafe for brakes
• Determining correct length; short but not too short, compare to old housing

Brakes

Anatomy

• Road: center-pull, single-pivot, dual-pivot
• Mountain: cantilever, straddle cable; linear-pull (v-brake), noodle
• Release mechanism
• Center adjust screw(s)
• Cartridge pads
• Disc

Pad Alignment

• Vertical; don't touch tire, or hang off the bottom of the rim
• Rotation; toe shouldn't point up or down
• Flat; surface should be parallel to rim face upon contact
• Toe-in; noise

Pad Maintenance

• Identify old dried out pads
• Filing off lip
• Metal deposits
• Re-surfacing; put the file on the table

Exercise

• Disconnect cable, remove pads, put barrel adjusters in middle
• Replace or file pads if necessary
• Re-install pads and position
• Re-connect cable and adjust tension

Braking Technique

• Use both
• Front does most of the stopping
• Shift weight back for hard braking/hills
• If rear wheel locks under hard braking, ease up on front rather than rear* puts more weight on rear

Wheel Truing

Anatomy

• Spokes; diameter, butting
• Nipples

Tools

• Stand; 3 knobs
• Dish tool
• Spoke wrenches; sizes

Types of Adjustment

• True
• Dish
• Round

Basic Principle

• Which way to turn nipples
• Triangle geometry
• Even numbers of spokes
• Turn 90d at a time; be aware of spoke twist

Technique

• Pick a high spot to work on
• Decide where it starts and ends
• Hold on to first spoke and count the rest
• Make adjustments
• Continue around rest of wheel before returning to the same spot

Rule #1: Avoid Cans of Worms

Cans of worms are any parts or problems with the bike that threaten to eat up unexpectedly large portions of time. It's up to your discretion to decide what you can and can't handle, but you might want to avoid the following:

• Serious rim problems
• Anything bent totally out of whack
• Excessively pitted bearing surfaces
• Cup and cone bottom brackets
• Suspension systems, pedal bearings
• Anything that you are not comfortable fixing or servicing
• Anything for which we lack the proper tools

These problems are outside the scope of a 12-hour class, and trying to fix them is a disservice to the students and to your sanity. If you run across a can of worms, suggest that they either bring it by during open hours or take it to a local bike shop.

Post Class Follow Up

You may consider having your students fill out a [survey of the class]. Put responses in the Classes folder in the office.

After you finish teaching the class, come back to this wiki page and update it with your experiences. Also, be sure to say some summarizing words on the Yahoo group because you and your co-instructor are probably the only Bike Kitchen regulars that have contact with the class.

Consider recruiting a fellow Bike Kitchen mechanic to teach the next session of the class. Tell them how fun it was!