Do you want to know the best BMX gear ratio for your riding style?
But first, who still remembers the 44/16 gearing?
Yup, although that may sound absurd to some, it once happened. But I can’t even imagine riding that MASSIVE sprocket now.
Were those really the good ol’ times? I highly doubt it, at least when it comes to BMX parts.
We wouldn’t have the freedom to ride as we do, and one of the biggest factors in unlocking more possibilities is a smaller sprocket.
This post covers:
What Is A Good BMX Gear Ratio?
| Gear ratio | Best for: |
| 25/9 | Technical street riding, quick acceleration |
| 28/9 | All-around riders who don’t want to pedal too much |
| 28/9+ | Going fast, riding transitions, etc. |
The classic BMX gearing (44/16) actually has one of the ideal sprocket and cog combinations at 55 gear inches.
Thus, even the modern gear ratios, although the sprockets are WAY smaller, have very similar gear ratios.
Whoever came up with this gear ratio nailed it!
The current most popular and closest to the classic gearing in modern BMX is 25/9 – that’s a 25-tooth sprocket and a 9-tooth rear hub cog.
It has 54.17 gear inches and is perfect for all the modern tech wizardry stuff because the front sprocket is small enough not to hit rails and ledges when grinding.
The second most popular is 28/9, with gear inches of 62.2.
It makes it slightly harder to pedal, which many riders prefer because it allows them to pick up speed much more quickly.
BMX Gear Ratio Chart
After analyzing 100+ riders, amateurs and pros, I came up with the most common modern BMX gearing that you can find in the table below.
| Gearing | Gear Inches |
| 25/9 | 55.5 |
| 28/9 | 62.2 |
| 29/9 | 64.4 |
| 30/9 | 66.6 |
| 32/9 | 71.1 |
I also wanted to give you some examples of professional riders and which gear ratios they prefer:
- Garrett Reynolds and Alex Kennedy ride a 25/9 gear ratio
- Broc Raiford and Courage Adams ride a 28/9 gear ratio
- Sergio Layos rides a 29/9 gear ratio
- Tom Dugan and Corey Walsh ride a 30/9 gear ratio
- Trey Jones rides a 32/9 gear ratio
Note: If you’re riding a freewheel, for instance, with a 13T cog, then the ideal front BMX sprocket size would be a 36T one. It will have 54 gear inches.
How Do I Know My BMX Gear Ratio?
Math time!
Although there are a few BMX gear calculators out there, you don’t need them to calculate your ratio.
Formula: (sprocket size/cog size) X wheel size.
Example: (25/9) X 20 = 55.5
An alternative unit to measure gearing is Roll Out. It’s how far your bike rolls with one crank rotation in inches.
Conclusion: The Right BMX Gear Ratio For You
I started with the 44/16 gear ratio and when all the way down to 25/9 over the period of 20+ years.
At some point, I was rocking a 24/9 (thanks to Animal’s Sprocky Balboa sprocket), but that was a little too easy to pedal.
In general, if you’re doing a lot of technical street riding or flatland, you’ll want a smaller front sprocket. This will make a lighter gear ratio.
On the other hand, if you like to go fast, pedal fast because you need speed for hitting ramps, trails and even street gaps, then a larger front sprocket and harder gearing will be best for you.
Quick recap:
- 25/9 gear ratio: For everyone who doesn’t need too much speed because technical wizardry is what you prefer. (But hey, you can still get the speed you need to pull insane gaps, you’ll just need to go more into “hamster” mode.)
- 28/9 gear ratio: For everyone who likes technical stuff and jumping stuff but doesn’t want to do too much pedaling.
- Anything above the 28/9: For everyone who’s all about speed. I don’t necessarily recommend it for street (if you mainly do grinds and stuff) because the initial crank is TOO hard.
Now you know which BMX gear ratio is best for you.
But I still recommend you test different rations.
Because you may think a 25/9 would be best for you, only to find that the 28/9 ratio is the sweet spot for your riding.
Pick up a friend’s bike and roll around – you don’t need to invest in getting multiple sprockets.
Further reading:
