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Bicycling for a better life
Cadence Made Easy
Better Speed and Endurance
Many years ago when I started getting serious about riding I worked out the details of better riding. One detail that definitely improved my speed and endurance was a good cadence. It became a part of my riding where I was no longer conscious of doing it. But with time I slowly neglected it and started attributing my lack of speed and endurance to age. This past winter I went through my old books and realized the many things I had worked out in my riding that had slowly disappeared, a high cadence being one. So I consciously worked on it. My minimum ride is now 64 miles three times a week.
Riding at a higher cadence does not mean simply pedaling faster. It is a pedaling rhythm. The idea is to get to a point where your normal pedaling is spinning without consciously being aware of it. Instead of just pushing down with each foot, you are also pulling with the other one. One description I read was think of a triangle. Your foot pushes down, then pulls back and up. It takes time and practice to develop this. But you want to get to the point where it is your normal pedalling.
At first you will feel tired sooner. That is because your heart is working harder. Of course you should check with your doctor before doing any strenuous riding, but bicycling is a great way to improve your heart rate. Starting out I could definitely feel my heart pounding but now I don't get tired at all. Now I am working on the pain of a long ride which is also slowly working itself out.
Cadence = RPM
Note: I have found several formulas and web sites, including Sheldon Browns, and while all calculate slightly differently all are within a few hundredths - good enough for 99% of us who ride.
Cadence is the revolutions per minute (RPM) you spin your pedals. This along with the chainring and rear sprocket produce speed. A very simple formula I found is .08 (for a road bike) x RPM x chainring teeth / sprocket teeth = MPH. For instance on my road bike pedaling at 100 RPM in the 39 tooth chainring and the 16 tooth sprocket I will be doing about 20 MPH (actual is 19.5). So I set my gear to 39/16 and ride 20 MPH. I know I will be doing at least 100 RPM.
| Pedaling RPM | Front Chainring | Rear Sprocket | = | MPH |
| 100 | 39 | 16 | | 19.5 |
It is interesting to note, if I drop my cadence down to 80 RPM my speed drops down to a whopping 16 MPH! Over a four hour ride that can be a huge difference. Plus, you are actually working harder.
| Pedaling RPM | Front Chainring | Rear Sprocket | = | MPH |
| 100 | 39 | 16 | | 19.5 |
| 80 | 39 | 16 | | 15.6 |
Figuring Your Cadence Gear
I have a three ring drive, 52/39/30. I never use my 30 (bought it with the bike for that just in case) and only use the 52 downhill. 90% of the time I use the 39 tooth chainring.
I should also point out that 39/15, 16, 17 are the straightest the chain can be which reduces friction.
The first thing is to find your cruising gear, that is the gear you are normally in on a relatively level road or pathway. For me it is the 39 tooth chainring and the 16 tooth rear sprocket. At a 100 RPM pedaling cadence I should be doing 20 MPH. You can easily figure this out by your cycling computer. Simply time yourself for 15 seconds and count the number of times your right (or left) foot comes to the top then multiply by 4. So if you count 25 pedaling strokes in 15 seconds you are doing 100 RPM.
If you are pedaling less then 100 RPM then you will need to drop down a gear until you can maintain 100 RPM. Before you give up and say that you prefer the speed over cadence lets look at a few numbers. In my 39/16 combination the calculation says 20 MPH at 100 RPM. If I drop to 80 RPM I will only be doing 16 MPH. BUT, if I drop to a 39/17 notice that at 100 RPM I should be riding at 18 MPH! Doesn't it make sense easier pedaling for faster speed?
| Pedaling RPM | Front Chainring | Rear Sprocket | = | MPH |
| 100 | 39 | 16 | | 19.5 |
| 80 | 39 | 16 | | 15.6 |
| 100 | 39 | 17 | | 18.46 |
Perfect Cadence
We aren't professional riders, in fact, not even 1% of the bicycle riding population makes a living at racing. Professionals have a cadence of 120 RPM, even 80 up hill. They also workout details in wind tunnels and other things that we will never be concerned about. So what is a perfect cadence? 100 RPM is not that hard to obtain. In fact, you will eventually find 105, 110 might be just right. But also, if you notice the calculations there is not a lot of difference between the 16 tooth sprocket and the 17. But it is not neccessary to be shifting all the time. In fact, it is probably not a good idea to be constantly shifting just for the wear and tear on the chain and gears. Here is what I find works for me.
First, I can usually maintain 20 MPH on level or slight grade with even some wind. Occasionally, I notice my speed may drop. This could be due to grabbing my water bottle, checking out the scenery, a gust of wind came up, or just daydreaming. I don't shift. If I maintain my speed between 18 and 21 MPH I stay in the 39/16 combination. In fact, I have tried, "for fun", to do an entire ride in that combo. Around Seattle it gets tiring with all the hills but the point is that there is a gear combo that you can spend most of your ride in.
But if I start cramping up, or have a good headwind and find my speed is down around 18 MPH or dropping I shift down to 39/17. Pedaling is easier and you won't get as tired. And it usually works out the cramping.
I prefer maintaing 20 MPH for long rides. It is hard to maintain a much faster speed for any length of time when getting into congested areas, stop signs and lights, or headwinds. But if I do get a long stretch, and especially if I have a tail wind, I shift to a faster gear when I can keep a pace over 21 MPH.
The end of my ride is usually 5 miles up hill. I just drop down to where I am pedaling easily and not bouncing around. While this could be my easiest combo, 39/27, I will find 39/24 or even 39/21 works well if I am not too tired.
Now when I ride I never need to work out my cadence. All I need to do is check my speed. If I keep it around 20 MPH in the 39/16 combo, I know my cadence is just right.
Other Points
Riding against the wind is much more bearable. If you run into a head wind just drop down a gear. You will be surprised to find it more enjoyable and you will probably be riding faster then you used too.
The same goes for hills. When you reach a hill you drop your gearing down. The difference with hills you aren't as interested in keeping a high RPM of 100 or maybe not even 80. I have read that even Lance Armstrong keeps a cadence of only 80 going up hill (pros also have a normal cadence of around 120 RPM). What is important is to keep some spin but not too much where you are bouncing around.
I see a lot of riders racing downhill. Unless you are riding down Snoqualmie pass for several miles, speeding downhill does not make up much time. The key is safe riding. It is also a good time to loosen up your legs. The fastest I go downhill is 30 MPH. I don't worry about cadence. Instead I set the gear so that I can still pedal to keep my legs loose but not bounce around.
Mountain biking and touring are different then regular road riding. The gearing on these types of bikes is set so that your cadence is usually high. There is not so much the concern for speed but easier riding. I road 120 miles with 95 lbs of bike and gear on my touring bike. I was riding on gravel so most of the time my speed was 10 to 15 MPH. But the ride was relatively easy even with all that weight due to a high cadence.
What Works For You
Some will argue against a high cadence for whatever reasons. But find what works for you. It has helped me ride further and enjoy longer rides and I feel better afterwards. And you may find other calculations with slightly different results. In fact, some go as far as to include crank length. I don't believe it needs to be that exact, you could include tire pressure, chain and gear quality, etc. Just calculate it while you ride, it's really pretty simple.
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