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Prototype - Evolving Daily

GT Speed Series 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.

$690.00 to $900.00 MSRP

What the maker states

Wheel size
Built for a 20" wheel (on 6 of 7 variants); Built for a 24" wheel (on 1 of 7 variants)
Top tube
Ranges from 18.5" to 22" (7 distinct values, across 7 of 7 variants)
Rear axle
15mm (on 4 of 7 variants); 10mm (on 3 of 7 variants)
Driver type
Driver cassette
Crank pieces
2-piece cranks
Spindle diameter
Spindle 24 mm spindle

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

7 verified variants

Variant groupJuniorExpertPro
VariantsSpeed Series JuniorSpeed Series Expert
Speed Series Expert XL
Speed Series Pro
Speed Series Pro XL
Speed Series Pro XXL
Speed Series Pro XL 24"
Wheel sizeBuilt for a 20" wheelBuilt for a 20" wheelBuilt for a 20" wheel (on 3 of 4 variants); Built for a 24" wheel (on 1 of 4 variants)
Top tube18.5"19.5" (on 1 of 2 variants); 20" (on 1 of 2 variants)20.75" (on 1 of 4 variants); 21.25" (on 1 of 4 variants); 21.75" (on 1 of 4 variants); 22" (on 1 of 4 variants)
Rear axle10mm10mm15mm
Size classJuniorExpert (on 1 of 2 variants); Expert-xl (on 1 of 2 variants)Pro-xl (on 2 of 4 variants); Pro (on 1 of 4 variants); Pro-xxl (on 1 of 4 variants)
Bottom bracket shellBottom-bracket shell euroBottom-bracket shell euroBottom-bracket shell bb86
Head tubeIntegrated-1Integrated-1-1/8Integrated-tapered-1-1/8-1.5
Driver typeDriver cassetteDriver cassetteDriver cassette
Driver teethDriver 16 teethDriver 16 teethDriver 16 teeth (on 3 of 4 variants); Driver 18 teeth (on 1 of 4 variants)
Price (MSRP)$690.00$690.00$900.00
Weightnot statednot statednot stated
Model year———
Price basisprice: MSRP confirmed against the manufacturerprice: MSRP confirmed against the manufacturerprice: MSRP confirmed against the manufacturer
Sourcemaker’s pagemaker’s page, maker’s pagemaker’s page, maker’s page
Last checked2026-08-102026-08-102026-08-10
Build with thisBuild with Speed Series JuniorBuild with Speed Series ExpertBuild with Speed Series Pro
What the maker states13 stated·2 not published
  • Built for a 20" wheel (on 6 of 7 variants); Built for a 24" wheel (on 1 of 7 variants).
  • Top tube ranges from 18.5" to 22" (7 distinct values, across 7 of 7 variants).
  • Rear axle 15mm (on 4 of 7 variants); Rear axle 10mm (on 3 of 7 variants).
  • Driver cassette.
  • 2-piece cranks.
  • Spindle 24 mm spindle.
  • Size class pro-xl (on 2 of 7 variants); Size class expert (on 1 of 7 variants); Size class expert-xl (on 1 of 7 variants); Size class junior (on 1 of 7 variants); and 2 further values across 2 of 7 variants.
  • Bottom-bracket shell bb86 (on 4 of 7 variants); Bottom-bracket shell euro (on 3 of 7 variants).
  • Head tube integrated-tapered-1-1/8-1.5 (on 4 of 7 variants); Head tube integrated-1-1/8 (on 2 of 7 variants); Head tube integrated-1 (on 1 of 7 variants).
  • Driver 16 teeth (on 6 of 7 variants); Driver 18 teeth (on 1 of 7 variants).
  • Sprocket 44 teeth (on 3 of 7 variants); Sprocket 42 teeth (on 2 of 7 variants); Sprocket 40 teeth (on 1 of 7 variants); Sprocket 41 teeth (on 1 of 7 variants).
  • Rear brake mount disc (on 4 of 7 variants).
  • Tire width 1.75 (on 4 of 7 variants); Tire width 1.375 (on 1 of 7 variants); Tire width 1.5 (on 1 of 7 variants).

2 further fields the checker looks for are not published by GT, so we leave them blank rather than estimate them, and those 2 checks stay silent on this complete bmx. They are seat system and front brake mount. 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

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