Hotrock 20 Coaster Boys
Part No.  

Hotrock 20 Coaster Boys

Part No.  106376
The Hotrock 20 Coaster is designed to be fun, safe, and reliable, with kid-friendly features like dependable brakes and low standover height.
  • Strong and durable alloy wheels can handle years of wear and tear.
  • The alloy V-Brakes provide reliable and excellent stopping power on the trail or on the road.
  • The tough, light, and durable Specialized A1 Premium Aluminum frame is built to last.

Technical Specifications

CHAIN KMC Z510, single speed, anti-drop, 1/2""x1/8""
BOTTOM BRACKET Steel, OPC Ball retainer type
CRANKSET Hi-Ten steel, OPC
FRONT HUB Steel, 3/8"" axle, 36h
REAR HUB Steel, coaster brake, nutted axle, 36h
INNER TUBES Standard, Schrader valve
SPOKES Stainless, 14g
RIMS 20"", alloy single wall, pin joint, 36h
FRONT TIRE Specialized Rhythm Lite, 2.0""
REAR TIRE Specialized Rhythm Lite, 2.0""
SADDLE Specialized Kids, 7mm rails, w/ clamp
SEATPOST Steel, 25.4mm
STEM Ahead, alloy, 1-1/8""
HANDLEBARS BMX, steel, 10-degree backsweep, 4-degree upsweep, 130mm rise, 22.2mm
GRIPS Specialized, Kraton, closed end, 105mm
BRAKE V-brake, alloy, linear pull
PEDALS Nylon, BMX style, loose ball bearings, 9/16"", w/ reflectors
HEADSET Ahead, 1/8"" sealed cartridge bearings
SEAT BINDER Alloy, 31.8mm
FORK Hi-Ten steel, 1-1/8"" threadless steerer, 3/8"" axle dropouts
FRAME Specialized A1 Premium Aluminum, 20"" singlespeed coaster, formed top tube/down tube, forged horizontal dropouts


Geometry Chart

- Geometry

Stem Length 37mm 37mm
Crank Length 114mm 114mm
Seatpost Length 220mm 220mm
Handlebar Width 560mm 560mm
Chainstay Length 386mm 386mm
Seat Tube Angle 72° 72°
Head Tube Angle 70° 70°
Rake 23.5mm 23.5mm
Head Tube Length 80mm 80mm
Top Tube Length (Actual) 438mm 446mm
Top Tube Length (Horizontal) 456mm 456mm
Seat Tube Length, Center to Top 241mm 241mm
Standover Height 505mm 476mm
Bottom Bracket Height 227mm 227mm