Helping You Ride Stronger, Look Better, and Feel Great!

Ask Levi: What Do Numbers On Chainrings Mean?

Today we have a simple question about chainrings on road bikes…

Hey Coach… different subject.

What do the numbers on the chainring mean? When I got my bike, I had the option of a ‘CHAINRINGS 53 x 39t’ or ‘CHAINRINGS 50 x 34t’

For whatever reason, I have the 53 x 39. What (if anything) does that indicate to you about my skill level? What are the advantages and disadvantages?

Thanks for your help. I really like your product reviews and comments.

-Charlie Chainring

Hi Charlie,

The first part of your question is very simple. The numbers on the chainrings simply refer to the number of teeth on each chainring. A standard crankset will have the 53 and 39 tooth rings (obviously the 53 tooth ring is the large one and the 39 tooth one is the small one,) while a compact crankset typically has 50 and 34 tooth rings.

As you probably realize, the more teeth on the chainring, the bigger the gear (i.e. it’s harder to pedal.)

Chainring size has no correlation with skill level, so the choice of rings on your bike doesn’t tell me much. Seeing the 53×39 might make some people think you’re a serious racer ready to really push the pace, but that would just be an assumption. Likewise, when some people see a compact crankset, they might think you’re an old man with bad knees. But again, that’s another assumption.

It’s entirely possible that someone could come in on a compact crankset and win the sprint to the finish line!

So the lesson there is that you can never judge a rider based on his choice of crankset, price of his bike, whether or not he shaves his legs, etc.

Now, on to the interesting debate – advantages and disadvantages of standard and compact cranksets.

Starting off with the standard 53×39 crankset. For many years, this was the only configuration you’d find on road bikes. Unless you went with a triple crankset, you were most likely riding a 53×39.

But not too long ago, compact cranksets (typically 50×34 or 50×36) took the market by storm. Now just about every road bike comes with the choice of standard or compact crankset.

Compact cranksets rose in popularity mainly because the lower gears made for a more comfortable ride in hilly or mountainous territory. The lower gears allow you to maintain a higher cadence while climbing, so you don’t tax your leg muscles as much. Also, many people have bad knees, and they find the lower gears to be much easier on their knees.

There are only two areas where a standard 53×39 crankset can outperform a compact:

1. High speed situations, such as sprinting and time trialing.

If you plan to go really fast on flat ground and don’t have too many long, steep hill climbs, you’re probably better with the standard crank. With the higher top gear, you have more potential speed at a given cadence.

It’s possible to go very fast on a compact crank by pedaling a very high cadence such as 150rpm, but if you’re up against someone with a standard crank, you better hope they can only push their big gear at 90rpm! (If both of you are pedaling at 150rpm, the rider with the bigger gear will win.)

2. Smooth shifting performance.

While the latest compact cranksets can be set up to shift smoothly, you’ll always get the best shifts with a standard double, with less effort during the setup and adjustment process.

It’s simple logic – the jump between a 53 and a 39 tooth ring is a 14 tooth difference. Between a 50 and 34, the chain has to jump a 16 tooth difference. It’s not much, but it’s there.

Should you switch?

Your 53×39 setup should be fine unless you feel the gears are too big/hard for the hills you climb regularly. That would be the only reason to switch if you were thinking about it. If you’re not struggling to push the gears, stick with what you have now.

Levi Bloom is an experienced endurance athlete who has been training and competing for over 17 years. A former Cat 1 road and mountain bike racer (professional class on the regional circuit), he is now a cycling coach (USA Cycling Level 3 Certified) and sports nutrition coach (Precision Nutrition Level 1 Certified).

More articles you will probably enjoy:

Leave a Reply

coach levi
Hi, I'm Coach Levi. I'm a USA Cycling Certified Level 3 Coach as well as Level 1 Certified with Precision Nutrition. Want to feel better, ride faster, and look great? Let's work together!

usa cycling certified coach


pn1 certified coach
Coach Levi is my favorite child and favorite cycling coach. I'd choose him over Christoper McCarmikael even. Did I mention that Levi can coach you to a healthier lifestyle where you look and feel your best?
Coach Levi's Mom
Hometown, PA