United Motocross BMX Bike

Regular price £479.99 £359.99 In Stock

United Motocross BMX Bike

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Regular price £479.99 £359.99 In Stock
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  • The Motocross pays homage to Bicycle Union, featuring inspiration and input from shared team riders. With a trails style geometry, sealed bearings throughout and a ton of aftermarket parts, the Motocross is ready to hit the trails or park straight out of the box.

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Product Specs
  1. FRAME MATERIAL: Cromo top tube, Hi-ten steel
  2. WHEEL SIZE: 20"
  4. CHAIN STAY LENGTH: 13.25"
  5. HEADTUBE ANGLE: 74.5°
  7. FORKS: Cromo steerer tube, 1020 Hi-Ten legs, integrated bearing race
  8. BARS: 9" X 29" 1020 Hi-Ten 1° up 12° back
  9. STEM: United 50mm reach top load
  10. HEADSET: United Sealed Integrated
  11. BRAKE MOUNTS: Welded
  13. FRONT HUB: 36H sealed female 10mm axle
  14. FRONT RIM: Alloy 36H single wall
  15. REAR HUB: 36H sealed alloy cassette with 14mm cromo axle and 9T 4 pawl driver
  16. REAR RIM: Alloy 36H single wall
  17. TYRES: United Direct 20" X 2.35"(front) & 2.1" (rear) - 65PSI
  18. SPROCKET: 28T Steel
  19. CRANKS: 170mm tubular, 8 spline with printed United logo
  20. BB: Seaed Mid
  21. PEDALS: United Supreme plastic
  22. SEAT: United padded seat/post combo with United sewn on patch
  23. GEARING: 28/9

Product Highlights
  • Longer top tube is great for taller riders who need a bit more room (6ft / 180cm plus)
  • Designed with more stable feeling geometry to suit trails and park riding
  • Sealed bearings throughout
  • Strong and durable crankset
  • High-quality aftermarket tires

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We have compiled a complete BMX buyers guide to help you through the process! Keep reading to find out more about your perfect BMX bike. Here at SourceBMX we are all riders, so we can offer advice that only 100% rider-owned BMX shops can - just ask.

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BMX bikes are measured in two ways: the size of the wheel (20” is the standard BMX wheel size), and the length of the frame which is gauged by the top tube measurement. We have also simplified for you into XS, Small, Medium, etc.

Here is a guide to what size you should be looking for - note that there is some overlap in sizes, as personal preference also comes into the equation!
Rider Height (in) Rider Height (cm ) Top Tube Length (in) 
2FT - 3FT 60 - 90cm 11.5" - 13"
2'8" - 3'4" 80 - 100 cm 2.8" - 15"
3FT - 3'8" 90 - 110cm 14.5" - 17"
3'6" - 4'6" 105 - 135cm 17" - 18.5"
4FT - 5'4" 120 - 160 18" - 25.25"
(XS - S)
5FT - 5'8" 150 - 170cm 20" - 20.5"
(S - M)
5'6" - 6FT 165 - 185cm 20.25" - 21"
(M - L)
6FT + 180cm + 20.75" +
(L - XL)

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