Bike Building: Part 2

By Rob Manning

Little but necessary parts.

Bike Build part 2 (continued from September)

When last we left you, we’d installed our BB and crankset, headset, fork, stem and bars. Now that we’ve got the majority of the larger parts attached to the bike, it’s time to begin installing the little things.

Shifters, Derailleurs and brake levers.

Your bars are really starting to look like something now.

A note on shifters/brake levers: Some people prefer to swap the order of installation of brake levers and shifters. However, this is a personal preference, but here are the basics for installation:

Assuming you’re building a geared bike, you’ll need something to move those derailleurs with. Here we’ve decided to use middle of the road, dependable Shimano Deore and LX parts for our derailleur system. To start with, we pull the shifters out of their box and inspect them for any readily apparent problems (such as broken or missing levers and cable plugs or problems with the shifting mechanism). Finding none we need to loosen the fixing bolt in order to slide the clamp over the bar. Remember that the triggers should be facing out towards the ends of the bars otherwise shifting will be a trial in itself. Leave the clamp bolts loose so that you can move the shifters around on the bar when you first sit on the bike.

Brake levers are the next item on the list to install. Depending on the kind of lever, you’ll have to loosen either one or two bolts before sliding the lever over the handlebar. If you’re using hydraulic brakes, ensure that you’re installing the rear brake on the right side of the bike and the front brake on the left side of the bike. With hydraulic brakes, you’ll want to lay the hydraulic lines in their holding fittings, called “braze on” fittings, as you route the line to the back of the bike.

Install the front caliper, but don't worry about alignment.

With the front brake hose and caliper (which clamps your rotor) hanging and the rear hose routed, we can start bolting them down. Route the front brake hose around the fork leg and bolt it to the fork. An adapter may be necessary, depending upon the kind of mounts the fork features. Check with your fork manufacturer and brake manufacturer to determine the adapter needed. They can often be purchased through your LBS as well. Don’t worry about aligning the caliper yet, we’ll deal with that soon enough. Once the front brake is bolted in place, move to the rear caliper and bolt that brake in place as well.

Derailleurs are going to be necessary to move the chain from one gear to another. Installing them is a lot easier than it sounds, especially since tuning will be left for last. To install the rear derailleur, simply back the B-limit screw (the one facing the back of the bike near the mounting bolt). With the B screw backed out, thread the derailleur mounting bolt onto the derailleur hanger and tighten it down. We’ll leave adjusting the limit screws until we tune the derailleur.

Derailleurs and brakes need to be bolted securely to the rear end.

The front derailleur requires a little more care in installation. Clamp the mounting band around the seat tube and thread in the bolt to keep it there. Now you’ll need to align the derailleur vertically and horizontally. The outer cage of the derailleur should be parallel to the chainrings of the crankset. If the cage is not properly aligned, shifting will suffer substantially. While adjusting the derailleur’s horizontal alignment, check the vertical alignment as well. The outer cage of the derailleur must be about 3 mm from the top of the teeth on the outer chainring. Slide the derailleur down the seat tube until the outer cage is 3 mm from the teeth of the big chainring and sits parallel to the outer chainring. Once alignment is complete, tighten down the pinch bolt on the clamp and admire your handy work.

Next month, we’ll take care of wheels, tires and tubes, rotors, cassette, chain and seat.