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What Are The Different BMX Crank Types?

bmx crank types

Do you want to know what the different BMX crank types are?

There are four styles available: 3-pc, 2.5-pc, 2-pc & 1-pc.

I explain below what are the main differences between them.

But I received the most questions about the 2.5-piece crank type, which is a more modern style.

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My recommendation: 2 (quickest installation) and 3 piece cranksets are the most reliable.

And absolutely never go with a 1-pc version. Even if you’re buying a complete BMX and it has a 1-pc spindle – JUST don’t!

Note: Don’t miss checking my ultimate collection of BMX cranks for every rider.

4 BMX Crank Types

3 Piece BMX Cranks

3 piece bmx cranks
A 3-piece crank is the most common amongst riders these days.

It consists of three separate pieces: two crank arms and a (splined) spindle.

You tighten each crank arm to the spindle with a bolt, which presses it together for smooth riding.

Note: Don’t tighten it too much because it’ll put too much pressure on the bearing and the cranks won’t spin as they should.

2.5 Piece BMX Cranks

2.5 piece bmx cranks
A 2.5 crank type is a more modern solution that, unlike a 2 piece crank, still has three separate parts.

The difference between a 2 and a 2.5 pc crankset is that the former has one arm integrated onto the spindle (or vice versa) and the latter has a moving one, with a “riveted system” at the end.

This allows you to change individual arms, whereas, with a 2-pc, you cannot.

2 Piece BMX Cranks

2 piece bmx cranks
A 2-pc BMX crank consists of a separate crank arm and an integrated spindle into the other crank arm.

This offers the quickest installation process, which is a big plus for me.

Downside: You cannot replace just the arm, but the whole set if you break or grind through the crank arm that’s integrated with the spindle.

1 Piece BMX Cranks

1 piece bmx cranks

These are becoming less and less popular but you can still see a 1-piece crankset on children’s bikes and cheap BMXs.

Both crank arms and the spindle are all one piece. (Nope, not even close to as strong as 2-3-piece cranks.)

I still remember how often did I need to fix my cranksets and bottom bracket when I first started riding BMX with a one-pc crank.


Compatible Crank Bottom Brackets

2-3 Piece Cranks

You’ll predominantly need a Mid bottom bracket for the majority of frames. (Be careful that you pick the right size because crank spindles vary in size (19mm, 22mm, 24mm).)

But, for instance, some Fly Bikes frames require a Spanish BB (so make sure you read specs and get the right size bearing.)

1 Piece Cranks

A bottom bracket in this case should be an American style – others do not fit.

Note: I also have a collection of the best and most quality BMX bottom brackets.

FAQs About BMX Crank Types

What are the main types of BMX cranks?

The main types of BMX cranks are 3-piece, 2-piece, and 1-piece cranks. 3-piece cranks consist of two individual crank arms and a spindle, offering high strength and ease of maintenance. 2-piece cranks have one crank arm and the spindle forged as a single piece, with the second arm being separate. 1-piece cranks are formed from a single piece of steel, curving around the bottom bracket, and are typically found on entry-level bikes.

How do I choose the right BMX crank length?

BMX crank length varies usually between 160mm to 180mm. Shorter cranks (160-170mm) provide better clearance for tricks and are preferred for street and park riding. Longer cranks (170-180mm) offer more leverage and are suited for BMX racing, trails or taller riders who need more pedaling power.

Are BMX cranks interchangeable among different types of BMX bikes?

Generally, BMX cranks are interchangeable among different BMX bikes, but compatibility depends on the bottom bracket size and type in your frame.

What materials are BMX cranks made from, and how do they differ?

BMX cranks are primarily made from steel or chromoly. Steel cranks are durable and affordable, making them suitable for entry-level bikes. Chromoly cranks offer a great balance of strength, durability, and lighter weight, ideal for freestyle and competitive riding.

How can I maintain my BMX cranks to ensure their longevity?

Regular maintenance includes keeping the cranks clean, checking for any signs of wear or damage, ensuring all bolts are tight and properly torqued, and periodically checking the bottom bracket for smooth operation. Lubricating the spindle and bottom bracket interface can also help prevent corrosion and wear

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About Author

Rok has been riding BMX for 20+ years, and when he's not having a session, he binges on videos, new product drops and works on creating the best content (sharing tips, tricks & more to make riding bikes easier for you) for The BMX Dude.