The Spoke Curriculum - Session 2: Difference between revisions

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== Bolts ==


=== Description ===
=== Description ===
Torque, lube


=== Details ===
=== Details ===
Very quick demo of how to make sure bolts don't seize. Righty-tighty, but mention that there are two parts on the bike that are "reverse threaded", and describe cross-threading.


=== Content ===
=== Content ===
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In general, if a bike component has threads (for screwing things on or off, such as bolts), then the threads should be greased so that parts won't seize together. Grease is thick, as opposed to oil, which is runny.
Most parts of the bike have a regular, "right-hand" thread. Turn clockwise to tighten, and counter-clockwise to loosen (remember: "righty-tighty, lefty-loosey").
Two parts normally don't, though. These have a left-hand thread and are "reverse threaded". The driveside (right) bottom bracket cup, and the non-driveside (left) pedal have reverse threads so that they don't unthread themselves from riding. These must be turned clockwise to remove them, and counter-clockwise to screw them in. If you're working on the pedals or the bottom bracket, always double-check that which way you need to turn the wrench!
Always thread parts in mostly by hand, and only use a tool once it starts to become snug. This prevents cross-threading (threading in a part at an angle, which cuts new threads through the old threads), since you can't apply enough force by hand to damage the threads. If a part is cross-threaded, special tools called taps are required to fix it, if it's fixable at all.
A rule of thumb for tightening parts is that you can turn them until they're snug, and then another 1/4 or 1/2 turn. Loose parts can fall out or cause damage from wiggling, while over-tightening parts can strip threads. Wrenches are generally sized to give an appropriate amount of leverage for the size of bolt: small bolts need less torque than big ones!
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== Free Repair ==
=== Description ===
Work through chart.
=== Details ===
Try to do it in a similar order to diagnosis; dependent on student interests and skills, but the order has some reason.