Are you trying to find the best BMX crank size for your riding style?
Various options are available, going from 160mm up to 175mm, which are the more traditional crank arm lengths. And spindle sizes, but more on that below.
But you can also find 150mm, 155mm and 180mm (and above) cranks – YUP, there’s something for everyone.
While 175mm was the standard back in the day, that’s not the case anymore.
In fact, there are fewer and fewer riders rocking “longer” cranks.
Most are transitioning to shorter because BMX freestyle is getting more and more technical. But there are other reasons why shorter crank arms are better (see below).
Plus, the EXTRA leverage of a longer crank arm isn’t necessary. The riders compensate it with a larger BMX sprocket (if needing to pedal fast to pull large gaps).
Note: Don’t forget to check my collection of the strongest BMX cranks.
But that may not be the case for trail dudes, although they may not necessarily need it (it’s more like a “cult following”). Oops, I said it.
This post covers:
- What is the ideal BMX crank length?
- Are longer or shorter cranks better?
- Are shorter/longer cranks faster?
- BMX crank spindle sizes
- Does BMX crank length matter?
And while many BMX crank size charts are out there, they’re not as relevant as they used to be.
What Is The Ideal BMX Crank Length?
Now here’s the tricky part: There’s really no right or wrong answer.
It’s really more of a personal preference. And what someone else rides might not suit you and vice versa.
Even if you’re a huge fan of a pro and like everything he does, the 160mm cranks he rides might not fit you right.
Are Longer Or Shorter Cranks Better?
Okay, unless you’re Sergio Layos, you don’t need long cranks. (By the way, Sergio rides 180mm cranks.)
Even anything above 170mm isn’t necessary; this goes for all – street, trail and park riders.
Longer cranks, 175mm+, are best for racing because they give you the extra leverage (especially jumping out of the gate) you need.
Fun fact: Some race dudes even have a slightly longer crank arm on the front foot side.
But one of the issues with longer cranks is that your back foot will be much closer to the rear axles.
So there’s a good chance of your heel hitting the peg because of how short modern BMX frames are. That wasn’t an issue in the “old days” because of the longer chainstays.
And if you have multi-hour long sessions, having legs further apart may feel more tiring. (But that’s not that big of a deal.)
Do I recommend longer cranks? Yes, if you’re into racing; otherwise, no.
Short BMX cranks are becoming the standard, and that’s because of the MANY benefits they bring.
Having your feet closer together means you will:
- Put less strain on your hips because you’ll be less “twisted”
- Catch and land tailwhips easier
- Pull a higher bunnyhop
- Not have to worry about hitting your back peg
The cranks are also stronger because the crank arms are shorter (less leverage).
Do I recommend shorter cranks? Yes.
And what’s best, when I went from 170mm to 160mm, I barely noticed it. But handling the bike became a lot more comfortable.
Lastly, 150mm cranks are more of a flatland thing but some freestyle dudes are already adopting them.
Are Shorter/Longer Cranks Faster?
If you are particularly interested in going fast, then yes, longer cranks are faster.
But this only really applies to racing or if you’re the type of rider that Corey Walsh is.
However, as mentioned above, you can switch to a larger sprocket but keep the short cranks. If you’re now on a 25T, go 28T (even 30T), and it’ll make a BIG difference.
You may also be interested in reading my article about the ideal BMX sprocket size.
BMX Crank Spindle Sizes
Besides the crank arm length, you should also pay close attention to the spindle size.
It won’t fit your BMX bottom bracket if you get the wrong size. Because a bottom bracket usually doesn’t come with cranks.
(But Sunday’s Saker cranks offer multiple lengths and come with a BB.)
BMX spindles come in three standard sizes: 19mm, 22mm and 24mm.
What’s the difference? The larger the diameter, the stronger the spindle.
Conclusion: Does BMX Crank Length Matter?
Yes, it does.
If you’re on the technical side of BMX, opting for a shorter crank will greatly help you. It did only good for me.
And don’t be scared to jump from 170mm to 160mm – you won’t feel it much. I didn’t, and I wouldn’t mind jumping from 175mm straight to 160mm.
But if you’re more a style and flow king where you do more pedaling than pumping, then yes, a longer, 175mm (or 180mm), cranks will do you well.
BMX cranks length recap:
- Short cranks: Technical street and park riding.
- Long cranks: Flow, style and going fast.