What BMX Crank Length Do I Need? (2025 Size Guide + Chart)

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?
• FAQs about BMX bike crank length

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 Bike Crank Length?

How to measure BMX bike 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.

Note: When we talk about crank length, it’s actually the crank arm length that’s important. And when we talk about crank size, it’s the spindle diameter we havve in mind.

BMX Cranks Size Chart

Below is a rough crank size chart for riders of different heights. But really, crank length is becoming more of a personal preference unless you’re into BMX racing.

For instance, I’m 5’11” and ride 160mm cranks.

Remember, gone are the days when we all rode 175mm cranks.

But if you need a general idea of the crank size, here’s the chart:

Are Longer Or Shorter Cranks Better?

Long BMX Crank Arm Length:

Okay, unless you’re Sergio Layos, you don’t need long cranks. (By the way, Sergio rides 180mm cranks.)

Yes, really.

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 (175-180mm); otherwise, no.

My long BMX cranks recommendation: Odyssey Thunderbolt cranks.

Short BMX Crank Arm Length:

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.

My short BMX cranks recommendation: Kink Brace cranks.

What About The Length Of BMX Race Cranks?

Here’s a handy BMX race crank size chart:

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.

Why?

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.

However, the only downside of 24mm crank spindles is that the bottom bracket is thinner, which can cause it to wear out faster.

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.

Crank it!

FAQs About BMX Bike Crank Length

What is the most common BMX crank size?

Most BMX riders use cranks between 170mm and 175mm, but shorter sizes (160–165mm) are becoming popular for technical street riding.

Do shorter cranks make tricks easier?

Yes. Shorter cranks give you more clearance for barspins, tailwhips, and grinds, making technical tricks feel smoother.

Are longer cranks better for speed?

Longer cranks (175mm+) give more leverage, which can help with sprinting and generating speed, especially for trails or racing.

Can I put any crank size on my BMX?

You can run different lengths, but you need to make sure they fit your frame’s bottom bracket and don’t interfere with chainstays.

What crank size is best for tall riders?

Taller riders often prefer 175mm cranks for extra leverage, but many still choose shorter options for more clearance in technical riding.

Do crank sizes affect bunnyhops?

Yes. Shorter cranks can make hops feel quicker and more controlled, while longer cranks can give you more power but feel less snappy.