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Radio Bikes Cobalt Complete BMX

What the checker saysnot checked

No fit check runs on a complete bike, and we will not pretend one does. A complete bike does not fill a slot in the builder, so the checker has no counterpart to compare it against and has never produced a single sentence about one.

Open it in the builder

The checker compares the dimensions listed in what we check, and what we don’t. “No conflicts found” means no conflict among those dimensions — not a guarantee that a build works. Errors mean it won’t fit; warnings mean it works but check; infos are notes.

$623.85 to $693.17 MSRP·7620 to 9780 g

What the maker states

Wheel size
Built for a 20" wheel
Top tube
Ranges from 17.5" to 21.25" (5 distinct values, across 5 of 5 variants)
Rear axle
10mm
Rear brake mount
V-brake
Driver type
Driver freewheel
Driver teeth
Driver 16 teeth

A value shown as a set or a range differs between this model’s variants and is never one variant’s spec.

5 verified variants

VariantTop tubeSize classHead tubePrice (MSRP)WeightSourceLast checkedBuild
Cobalt Mini17.5"miniintegrated-1$646.967730 gmaker’s page2026-08-10Build with this
Cobalt Junior18.5"juniorintegrated-1$623.857620 gmaker’s page2026-08-10Build with this
Cobalt Expert19.5"expertintegrated-1-1/8$681.628820 gmaker’s page2026-08-10Build with this
Cobalt Pro20.75"prointegrated-1-1/8$670.069780 gmaker’s page2026-08-10Build with this
Cobalt Pro XL21.25"pro-xlintegrated-1-1/8$693.179780 gmaker’s page2026-08-10Build with this
What the maker states11 stated·4 not published
  • Built for a 20" wheel.
  • Top tube ranges from 17.5" to 21.25" (5 distinct values, across 5 of 5 variants).
  • Rear axle 10mm.
  • Rear brake mount v-brake.
  • Driver freewheel.
  • Driver 16 teeth.
  • 3-piece cranks.
  • Size class expert (on 1 of 5 variants); Size class junior (on 1 of 5 variants); Size class mini (on 1 of 5 variants); Size class pro (on 1 of 5 variants); and 1 further value across 1 of 5 variants.
  • Head tube integrated-1-1/8 (on 3 of 5 variants); Head tube integrated-1 (on 2 of 5 variants).
  • Sprocket 44 teeth (on 2 of 5 variants); Sprocket 38 teeth (on 1 of 5 variants); Sprocket 40 teeth (on 1 of 5 variants); Sprocket 42 teeth (on 1 of 5 variants).
  • Tire width 1.125 (on 2 of 5 variants); Tire width 1.375 (on 1 of 5 variants).

4 further fields the checker looks for are not published by Radio Bikes, so we leave them blank rather than estimate them, and those 4 checks stay silent on this complete bmx. They are bottom bracket shell, seat system, front brake mount and spindle diameter. Each is recorded as “not stated by the maker (not checked)”.

Source: each variant links the maker’s own page in the table above. Last checked 2026-08-10.

Where this sits

Radio Bikes Cobalt is the first model on that list.Next: Radio Bikes Quartz Carbonic ProAll Radio Bikes complete bmxsOpen the BMX builder