What is the difference in bottom bracket sizes?


So recently I ran into an issue where I bent my titanium profile spindle. Devastating right? I had a few options: I could buy a new set of Demolition rig cranks for $180. Or I could buy a new Ti-spindle for $170. To be honest, getting a whole set of cranks for the price of a spindle seemed like a killer deal. Until I realized that the rig cranks were 24mm and I was running a 19mm. I thought I’d put together a little post about the difference here…

Overview

It is super important to understand the difference in 19mm and 22mm. Most beginners rush right in to buying new parts for their bike, without fully understanding whats going on. This could cost you hundreds in the long run.

19mm

Referring to the picture beside us, the 19mm is just the size of the opening. A 19mm bottom bracket will only work with 19mm cranks. 19mm is becoming kind of old school. But there’s nothing wrong running 19mm.

Pros

  • Very common
  • A lot of common cranks have a 19mm spindle.

Cons

  • Spindles are smaller, therefore they are weaker
  • Unnoticeably heavier than 22mm.

19mm Cranks and Bottom Brackets

22mm

A 22mm bottom bracket only has a 3mm larger diameter. All this means is that you can’t run 19mm spindles on the bottom bracket. Since the opening is a little bigger, there is very very minuscule weight savings.

However, most weight savings will come with a more hollow 22mm spindle. We will talk about spindles later.

Pros

  • Lighter and stronger cranks are usually associated with 22mm bottom brackets
  • same price as 19mm

Cons

  • Slightly less common than 19mm
  • Might have a hard time finding replacement parts if you are desperate

22mm Cranks and Bottom Brackets

24mm

I’m actually just learning about these. This is 5mm bigger than the common 19mm bottom bracket. From what I can tell, the 24mm bottom brackets are a tiny bit more expensive than the 19 and 22.

Pros

  • Tiny bit lighter than the other sizes
  • Stronger spindles come in this size

Cons

  • A little more expensive
  • Harder to find than other sizes

24mm Cranks and Bottom Brackets

Spindles

19mm Spindle

The most common bmx spindle size. People upgrade to a 22mm or a 24mm if they have problems with breaking their 19mm spindle. A lot of times the bigger spindles are more hollow and will save weight. I ride a 19mm spindle and have only broken the titanium profile spindle. The normal chromoly GHD spindles never give me problems.

22mm Spindle

This is the spindle size of most “indestructible cranks”. Famous strong cranks like the Profile Column, Animal Akimbo, and Odyssey Calibur boast that they can really take a beating. It really is a bad day when you snap a crank arm or spindle after doing a massive drop.

Side note: Look at these cranks

While doing research I came across this ad and props to Odyssey for including a bb with their Calibur cranks. These look fresh.

24mm Spindle

There isn’t a whole lot of cranks this size. The ones that do come in 24mm are really top line cranks. Hefty street riders prefer beefy 24mm cranks. My favorite ones are the Demolition Rig Cranks.

Yep, that’s right, Dennis Enarson’s RIG cranks (and the rest of his parts) can handle literally whatever you throw at them. Proof is in the pudding if you’ve seen Dennis’ latest #CAPSLOCK video and this banger photo in particular. How f-n crazy is this.

Demolition.com

Watch CAPS LOCK HERE

Anyway, for me personally, I don’t go hard enough for 24mm cranks. My body would break long before my cranks haha.

What’s Right for you?

Here is a flow chart that you can use to decide the best fit for you. But in reality… get whatever cranks you want. This chart is made for practicality so you don’t spend $200 on a set of beefy cranks for no reason. However, if you want beefy cranks for no reason, by all means get them.

What’s Next?

Douglas Laird

Douglas is a 23-year-old BMX rider who got his first true BMX bike for his 13th birthday and has been riding nonstop for over 10 years. “Bmx has taken me too well over a hundred skateparks across multiple states and countries.” Dougsterbob.com was born to help people understand the sport that has changed my life for the better. My goal is to help you with everything BMX related. With over 200 BMX posts and counting, dougsterbob.com is quickly growing to be one of the best bmx related websites.

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