13: Putting the Pedal to the Metal: The Drivetrain in .NET framework

Encode Quick Response Code in .NET framework 13: Putting the Pedal to the Metal: The Drivetrain

Many pedals are marked with an L or an R to help you figure out which pedal should go on which side You want to make sure you have the correct pedal, because the left pedal unscrews in a clockwise direction and the right pedal unscrews counterclockwise If you try to screw in the wrong pedal, you ll damage the threads To install new pedals, follow these steps: 1 Apply grease to the threads of each pedal (as shown in Figure 13-3) 2 Start with the right pedal, and remember that you ll be turning the pedal in a clockwise direction 3 To ensure that you don t damage any threads, screw the pedal in by hand using care (as is shown in Figure 13-4)

4 When the threads engage, use the wrench to tighten the pedal One way to tighten the pedal is to use one hand to keep the wrench on the pedal s wrench flats and then, with the other hand, rotate the opposite crank arm to tighten Tighten until the pedals are secure, but don t overtighten Carefully check the crank arm for any metal shavings at the base of the pedal and, if necessary, remove them with a file 5 Repeat steps 1 through 4 for the left pedal, except screwing it in a counterclockwise direction to tighten

The two major components of the drivetrain are the crankset and the bottom bracket (see Figure 13-5) In this section, we explain how to service different types of crank arms and the two major types of bottom brackets cartridges and adjustable bottom brackets

The crankset plays the leading role in moving you forward when you bike Consisting of the cranks, the chainrings, and the bottom bracket assembly, the crankset s job is to transfer power with the chain from your legs and the pedals to the chain and back to the rear wheel On the crankset, the crank and chainrings play important roles The cranks are what connect the pedals to the bike, and the chainrings guide the chain as it receives the force from the turning cranks Of the different cranksets on the market, there are three main categories: One-piece: Children s bikes and some low-end adult bikes have onepiece cranksets, where the crank arms are one, long, S-shaped piece and the bottom bracket has two large bearing retainers that are serviceable and adjustable One-piece crankset are made to be fairly durable to hold up to the kind of abuse a kid can dish out on bike, but as you might expect for a low-end product, they re heavy and not designed for performance

Cottered: Older bikes tend to have cottered cranksets These consist of separate crank arms that are attached to the bottom bracket axle using a tapered metal pin A hammer or a special tool is used to put these pins in place, after which nuts are attached to keep them secure Cotterless: Newer bikes are built with cotterless cranksets These are higher-performance parts with crank arms that come in a variety of sizes and styles and are built from more expensive materials that are lighter and stronger Cotterless cranks are held in place by a nut or a bolt or in some cases by pinch bolts on the left-side crank In the following sections, we tell you how to remove and install all three types so you can work on them

To remove a one-piece crankset, follow these steps: 1 Use a wrench to unscrew the lockring in a clockwise direction 2 When it s loose, remove it by lifting it over the crank arm 3 Place a chisel in the slot of the slotted retainer, which sits under the lockring 4 Tap the chisel lightly with a hammer in a clockwise direction 5 When it s loose, remove it by lifting it over the crank arm 6 Pull the entire crank assembly out of the bottom bracket shell 7 Use the chisel and hammer to lightly knock out the bearing cups that sit within the bottom-bracket shell To install the one piece crankset, follow these procedures in reverse