The mechanics of shifting is one of those things about cycling that can seem confusing at first, but in a short time becomes second nature. Then once you understand how shifting relates to cadence, you become much more effective at using gears to ride faster and save energy. Win-win!
Basic gear selection
Like in the photo above, most modern road bikes have two chainrings in the front, and a 9, 10, or 11 speed cassette in the rear. These are your gears, and they allow you to climb more easily, go faster downhill, and ride almost any terrain.
The left shifter is for the front derailleur and the front chain rings, which are your biggest changes in gear. The right shifter is for your rear derailleur and your rear cogs (or cassette), which are your smaller changes in gear. Left=Front=Big. Right=Rear=Small.
Start in a gear that’s appropriate for your terrain. In general:
- For uphills and headwinds: Use small front chainring + bigger rear cogs.
- For downhills and flats: Use large front chainring + a range of rear cogs.
Once you’re going, use your rear shifter to select and fine tune your cadence. Your cadence is the number of times per minute you rotate the pedals (measured in RPM’s), and is the secret to riding faster for longer periods of time.
Cadence is the reason you choose one gear over another.
This is important because understanding cadence is key to making good decisions with shifting. It is a calculation based on how you’re feeling, the slope of the road, the wind conditions, the group you’re with, the intensity of the ride, your fitness level, and a variety of other factors.
Once you know how it all works together, the right combination of shifting and cadence allows you to minimize muscular fatigue, build aerobic endurance, and ultimately go faster with less effort. When coaches say “Spin to win,” this is what we’re talking about.
A good general guideline for cadence is 85-100 RPM. This allows you to use less force per pedal stroke and helps you more easily adjust to changing conditions. When climbing hills it can go a little lower, around 70-85 RPM depending on the length and grade of the terrain.
As you ride, notice how small changes in your rear shifting affects how fast or slow you are pedaling. When your gear is even just a little too big, you end up pushing harder and your cadence slows down. If the gear is too easy, you spin out. Your optimal cadence is the balance between these two scenarios. You want enough resistance to maintain your speed, but in an easy enough gear that your legs spin efficiently.
Some other tricks with shifting
Cross-gearing (or cross-chaining) is when you are in Big-Big or Small-Small. This means you are in the big ring up front and the biggest cog in the back, or the small ring up front and the small cog in back. It puts undue stress on your drivetrain, and that usually results in your gears making more noise than usual. In general, if you are cross-geared it means you need to shift to your other front chainring and find a similar gear with the rear cassette (see below). This way if you need to shift again, you’re not at the end of your gear range. You also save wear and tear on the moving parts.
Shift before you need to by reading the road and planning ahead. If you’re riding on a flat section of road in your big chain ring but you see a hill coming, switch to your small chainring in front to prepare for the climb. As you do this, shift into a slightly harder cog in the rear to keep your cadence relatively the same and avoid an interruption in your pedaling. Same with going downhill. Shift into your big chain ring ahead of time but shift in an easier cog in the rear to keep your cadence relatively the same. I rarely shift front derailleur all by itself– preferring instead to shift the rear first to accommodate the abrupt change from the front.
Always Be Pedaling
Anticipating your shifts allows you to always be pedaling. Even on downhills. Proper road cyclists always keep their legs moving, even if they are soft pedaling. Coasting is considered bad technique unless it’s for brief periods of time when it’s unsafe to keep pedaling (think fast downhills or riding in traffic). Your small chainring allows you to pedal up most hills. Your big chainring allows you to pedal down most descents. Keeping your legs moving signals to other riders that you know what you’re doing, and keeps your legs fresh. If you’re in the habit of not pedaling on downhills, work to change that. Keeping your legs moving will help you gain fitness and become a more adept rider.
Practice Makes Perfect
If pedaling at a high cadence and finding the right gear seems difficult at first, don’t get discouraged. Shifting takes practice and riding with a higher cadence is something that needs to be trained over time. There are drills that cyclists do to increase their leg speed, same as runners. It can also take some time to learn your own tricks when it comes to effective shifting techniques. Paying attention to these things every time you ride will pay dividends in the long run.
Computers are your Friend
If you don’t already have a computer that measures cadence, it’s a smart investment. It is very hard to feel how fast you’re pedaling unless you’ve been riding a number of years. Everyone has their own sweet spot that you will figure out with time. A basic cycling computer that measures cadence is around $60. If you pay attention to it you will learn a lot about your own strengths and weaknesses just from that one metric.
Join us for an on-the-bike Shifting and Cadence Skills Clinic in Prospect Park on Wednesday, July 1!
Update June 19, 2015:
This article was republished on Active.com.