Road bike shifters could be the most efficient mechanism on earth for transferring human energy to a machine. Shifters and derailleurs have been around for many years, and developed into relatively complex machines.
What Road Bike Shifters Do For You
Road bike shifters and gears make it possible to maintain motion and speed by being in the correct gear on your bike no matter the terrain, wind or weather. When used properly, shifters make it easier on the knees, lungs, heart and they prolong the life of your chain, cassette and body.
Gears and Efficiency
With a stack of gears on the front and back, shifting can seem intimidating but they serve to tame the confusion. Understanding the basics about road bike shifters goes a long way to keep you moving at a steady pace up hills and to find that comfortable gear to grind out long miles on flat ground.
Left Shifter, Front Gears
Road bike shifters have standard configurations. The shifter on the left side controls the front gears, also known as chainrings. It has either two or three positions which moves the the chain up or down accordingly. Bikes with two gears up front are known as a “standard or compact-double” Bikes with three gears up front are referred to as a “triple.”
Right Shifter, Back Gears
The road bike shifter on the right side controls the gears on your back wheel. Older road bikes may have only seven or eight gears in the back. Contemporary road bikes typically employ 9, 10 or 11 gears in back. The right-side drivetrain shifters are more complicated because they have more work to do, in a smaller space.
How Road Bike Shifters Work
Road bike shifters work by releasing or adding tension to a cable attached to a derailleur. When the rider operates the shifter, the tension is changed, and the derailleur moves the chain up or down, switching the chain to a different gear.
Positioned by Index
The vast majority of modern shifters are indexed. This means that each time you click the shifter with your fingers or thumb, the shifter allows the cable to move a precise amount equivalent to one gear shift.
Old-school shifters did not have indexing, the rider determined when the bike shifted by feel and how it sounded. Also known as friction shifters, they are still around today on some bikes, but are considered antiquated.
Most modern road bikes employ one of three different brands of indexing shifters: Shimano, Campagnolo and SRAM, with Shimano being at the top of the market numbers wise for standard production bikes. High-end bikes often rely on Campy or SRAM, but Shimano also has that covered too. The three top brands look similar, and are positioned in the same place, but the actual functioning or mechanism of the shifting levers differ.
Shimano designed the STi (Shimano Total Integration) system, which is a brake lever and shifter integrated into one unit. Cyclists shift to larger sprockets by pressing the brake lever sideways. Downshifting is done by pressing a small, separate lever behind the brake lever.
SRAM uses a single lever to shift gears up and down. Tapping the lever inward a short distance on the right shifter shifts the rear derailleur down. Pushing that same lever further inward produces an up-shift on the rear derailleur. The front shifter is reversed as a small tap shifts down while a larger sweet shifts up to the big chain ring.
Rather than using the brake lever to shift up like Shimano, Campy uses a small lever behind the brake lever to shift up. A small button inside the hood is used to shift down. Because Campy is indexed on the right side only, it’s compatible with any chainring, unlike Shimano and SRAM, which must be specifically matched to the size and number of chainrings used.
Which One is Best
When choosing between road bike shifter brands, it depends on the existing groupset that you use. The shifter should correspond to the other components on your bike. For example: Shimano shifters are designed to work with Shimano components. The best way to choose your road bike shifter is to try them before purchasing to see which one you find more comfortable, and which lever system you prefer. It’s also a matter of how much you can afford.
Handlebar and Shifter Position
Shifter and handlebar position is a personal preference; there’s no wrong way to do it within reason if the position is comfortable for you. Old-school set-ups typically have the drops horizontal, but it’s common these days to see the drops pointed down somewhat. Find a happy medium for your handlebars, and then adjust the shifters/hoods from there.
Adjust the Position
It might be necessary, depending on how much you want to move the shifters, to remove or loosen the bar tape. You might be able to get by with minor adjustments without disturbing it. Begin by slipping a 5-mm hex wrench under the rubber brake hood to loosen the hoods via a small hex bolt. Sit on the bike, grasp the hoods, move them as needed, and then snug each clamp bolt just enough to hold the position.
Not Too Tight
Don’t over-tighten shifters on the bars. They should be tight enough so that they won’t slide when you put your full weight on them, but loose enough so that you can still twist them if you apply enough force. The idea is to allow them to move in a crash instead of breaking.
Clean and Degrease
Peel back the rubber shifter hoods so that you have access to the guts of the shifter. Use an evaporative degreaser to remove the grit and accumulated caked grease in the shifter mechanism. Don’t be afraid to get dirty. It may take quite a bit of the degreaser to get the shifters to loosen up. If you have access to pressurized air, use that lightly to blow out dirt and gunk. Run the shifter through the gears to work it in after spraying the degreaser. Repeat the process until the shifters are functioning normaly.
Lube and Ride
Lube the shifter with a light, bicycle-specific spray lube. Let the bike sit for an hour to allow the solvents to evaporate. Replace the road bike shifter hoods and go for a ride with well functioning shifting.