Light quick 20“ bike with a lightweight alloy fork and V-brakes for fun rides in easy terrain. Light wheelset makes the bike easier to move, which helps your little bikers with riding uphill. Thunder 20 is equipped with new MicroSHIFT gear that is easy to control, as well as quality Schwalbe tires with reflective tape for better road safety.
  • Junior Trail Geometry and 100% fun factor design approach
  • Lightweight alloy fork
  • MicroSHIFT 1x7 28 x 12-28
  • Tires Schwalbe CX Comp, 20x1.75" with Reflective tape

  • COLOUR Gloss Dark Red/Black/White, Gloss Neon Cyan/Black/Orange
  • FRAME Alloy Al-6061 T6 Custom tubing, Junior Trail Geometry, Shark Spine Semi 20", OLD 130x9, BB BSA 68mm, V-brake pivots, Fender Ready Dropout, Replaceable RD Hanger
  • HEAD SET CH290TBW, 1-1/8"
  • FORK Thunder 20", Alloy Custom Tubing, Ahead 1-1/8", V-Brake, QR Type
  • SIZES 10.0"

  • GEARS 1×7, 28×12-28, 233 %
  • SHIFTER microSHIFT DS45-7R, 7-speed
  • REAR DERAILLEUR microSHIFT RD-M21SS, Super Short cage
  • CRANKSET Wheel Top SXB4BL-MS, 28T
  • BOTTOM BRACKET Thun Topaz 120mm, BSA, shell 68mm
  • CHAIN KMC Z8.3
  • PEDALS Marwi SP-202

  • HANDLEBAR ONE1 Alloy, MTB AL-153BT, 10° backsweep, 30mm rise, 560mm, 25.4mm
  • STEM ONE1 MAS-M60368 Alloy, 25.4xE35mm, 15°
  • GRIPS Velo VL-G311
  • BRAKES Tektro V-brakes
  • SADDLE ONE1 Junior
  • SEAT POST ONE1 Alloy, SP C207, 27.2x230mm

  • FRONT HUB ONE1 KTA55F, 20H, M9x100mm, QR Type
  • REAR HUB ONE1 KTAZ2R, 20H, M10x130, CASSETE, QR Type
  • RIMS Stars J19SD, 20H
  • TIRES Schwalbe CX Comp, 20x1.75", Reflective tape
  • SPOKES Sapim Galvanized Black

  • Total WEIGHT* 8.4 Kg

Weight is set for M sized frame unless stated otherwise. We focus on maximum reliability, so cutting some grams down is not our priority! The weight is measured as the each bike specification shows.

Frame Size 10"
Rider Size (CM) 10": 110 – 130
Wheels size 10": 20"
CHAINSTAY LENGTH (mm) 10": 350
REAch (mm) 10": 335
STACK HEIGHT (MM) 10": 409
bb drop (mm) 10": 10
WHEELBASE (mm) 10": 870
head tube angle degree 10": 70
seat tube angle degree 10": 73
HEAD TUBE LENGTH (mm) 10": 110
SEAT TUBE LENGTH (mm) 10": 255
SEAT Post LENGTH / TRAVEL (mm) 10": 230
Handlebar Width (mm) 10": 560 - R30
Stem Length (mm) 10": 35
Crank Length (mm) 10": 127
Number BFI Code Description
999 013.0002.00110-244 Rear derailleur hanger

2022 NOTE: Due to the pandemic and difficulties in the delivery chain arising worldwide & extreme demand for our bikes at the same time, we reserve the right to replace some parts with those at the same level of performance (e.g. different brand, the same level of parts) to keep the overall quality of our bicycles. We’re sorry about that. At the end of the day, riding a bike is the best way of #staypositive ever, no matter what brand your handlebar or any other part is!

Manufacturers reserve the right to vary specifiations, including colors, with or without notice at such times in such manner as deemed appropriate. Major as well as minor changes may be involved. Every effort, however, is made to ensure the accuracy of the particulars contained in this presentation. Consult your Dealer for details regarding the specifications of any featured product. This presentation shall not constitute - under any circumstances whatsoever - an offer by the Company to any individual. All sales are made by the Distributor or Dealer subject to and with the benefit of the standard Conditions of Sale and Warranty provided by the Distributor or Dealer, copies of which may be obtained upon request. While efforts are made to ensure specification accuracy cannot always immediately reflect either change in specification or in some isolated cases the provision of a particular feature. Customers are always advised to discuss specific details with the supplying Dealer, especially if a selection is dependent upon one of the features advertised.* The range of the e-bike depends on many factors such as the rider's weight, the track profile, the level of assistance, gear settings, the wind, etc., so the information is indicative and may vary.

Nearest shops

Kola Pešek a syn I

1034 km away

U Elekrárny 306

53002 Pardubice - Čeperka

Picton Cycles

5673 km away

High St 11-13

L15 8HE Liverpool

Brattørkaia Sykkel AS

6094 km away

Brattørkaia 15AB

7010 Trondheim

VOF Fietsen Opsomer

6155 km away

Hillesteenweg 20

8750 Wingene

Tel.: 0032-51612755

We strongly recommend buying our products from authorized dealers only.

Professionals who can advise you the best bike fits your riding style and subsequent service.

Consider these

Rock Machine Research&Development

Passion. Mission.

If you want to burn, be on fire! From the first pencil sketch, through prototype testing and debugging to the finished product tested in the most rigorous labs by the engineers and on the trails by our ambassadors and us.

See you on the trail!

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