A crank has one job: revolve. The Speedline Spinners rebuilds the part that does it. It is a hybrid — a cold forged hollow aluminum arm with a Toray T700S carbon fiber back bone bonded to it. The aluminum handles the abuse, the threads and the crash landings. The carbon spine runs down the back of the arm and fights the flex that shows up when a rider stands and stomps. It is the first hybrid BMX crank we know of.

The hollow cold forged arm increases rigidity for maximum holeshot potential while staying light enough to spin fast on the track. We ran a narrow Q-factor to help that along. The hollow 30mm heat-treated 7075 aluminum spindle works with almost every BB shell type imaginable and ships with a T47 sealed bearing bottom bracket included (BSA EB30 optional).

The removable spider accepts all 104 BCD chainrings. No chainring included.

What we changed on the new version

We changed the forging tool twice during development. Anybody who has paid for a forging die knows what that costs. We did it to pull weight out of the places not carrying load and put strength back into the ones that were. The arm you bolt on is the third shape we made, not the first one that worked.

Rider input came from Maris Strombergs, Kye Whyte, Oli Moran, Gaige Gomolicke and Justin Perkins. Those five race at a level where a bad crank shows up inside one lap.

Independent fatigue testing

1,300 Nm. That is 959 lb-ft. The number comes out of two separate dynamic fatigue tests, both run as independent third-party testing to EN 16054:2012, with the machine record also citing ISO 4210-3.

• Test 1 — March 26, 2026. Load at 45 degrees, 100,000 cycles. Pass. No failure, no visible cracks.
• Test 2 — March 31, 2026. Same setup at 30 degrees, 100,000 cycles. Pass.

They tested the 180mm arm — the longest we make, and the worst case, since a longer arm puts a bigger bending moment into the spindle. It passed both, clean.

Specifications

• Price: $399.95
• Weight: 739 g / 26.1 oz — this is a 180mm set including the spindle, the longest and therefore heaviest length. Shorter sets weigh less.
• Crank lengths: 165, 167.5, 170, 172.5, 175, 177.5 and 180mm
• Finishes: Black Anodized with gloss and matte areas · Silver Anodized with polished and matte areas
• Arm: Cold forged hollow aluminum with bonded Toray T700S carbon back bone
• Spindle: Hollow 30mm, 7075 heat-treated aluminum
• Bore: 30mm
• Bottom bracket: Included — T47 30mm or BSA EB30
• Crankset style: 2-piece
• Chainring BCD: 104, removable spider. Single chainring, not included.
• Pedal spindle: 9/16"
• Drive side: Right-hand drive
• Availability: On sale October 2026

Want the full breakdown against our Elite Carbon cranks, including crank length guidance and how leverage actually works? Read The New Speedline Spinners vs Elite Carbon Cranks.