Why buy your bike from Sigma Sports?
Don't hesitate to reach out to us. It's our goal to answer all of your questions and offer the best advice from our experts. We’ll be happy to answer any questions you may have. Contact us now or visit us in-store.
All our bikes are fully built by our Cytech qualified mechanics. To find out more, see the Built, Checked, Tuned and Tested section below to see how we'll deliver your bike.
We offer FREE DELIVERY of your bike to your home or place of work. Once you've placed your order, our Customer Care team will be in contact to offer a convenient delivery date of your choice.
We've partnered with Pedalsure to offer you 30-DAYS FREE bike insurance on new bikes over £400. Visit our Cycle Insurance page to learn more and claim.
BMC Twostroke AL 20" Kids Mountain Bike 2022
Reliable, safe and robust, the BMC Twostroke AL 20" is a kids mountain bike ideal for young trail explorers. At the heart of the bike is a light, strong aluminium frameset that offers an enlivening ride experience and is more than resilient enough for the bumps and scrapes associated with off-road riding.
The frame size is perfect for children between 110cm and 135cm in height and features a geometry that takes cues from BMC's adult mountain bikes but adapts it for children to grant more predictable handling. Robust but light 20" wheels make changing direction easy, and the voluminous, grippy tyres inspire confidence when cornering on rough tracks. Flat handlebars afford further control by positioning the rider in a comfortable and relaxed position.
SRAM 1 x 8-speed gears offer a broad range of ratios to make any hill conquerable and are easy to use, thanks to their trigger shifters. Matching SRAM hydraulic disc brakes are powerful in all weather conditions, and their short reach levers make modulation effortless when in small hands.
- A lightweight and confidence-inspiring MTB designed to let 5 to 8-year-olds explore with more fun and control
- The size is perfect for children who are between 110cm and 135cm tall (3’ 7” - 4’ 5”)
- An aluminium frameset is light and robust, and its powder-coated finish is highly durable
- The geometry is inspired by BMC’s adult MTBs but is adapted for smaller riders to guarantee intuitive and reliable riding
- Strong but light 20” wheels and wide, grippy Kenda tyres improve handling on off-road surfaces
- SRAM 1 x 8-speed gears are wide-ranging, accurate and easy to use thanks to their trigger-lever operation
- TEKTRO hydraulic disc brakes and short reach levers make stopping easy and controlled
- Flat handlebars increase steering predictability
|Frame||BMC Twostroke AL 20” lightweight aluminium with powder coat finish,1 1/8" head tube, BSA threaded bottom bracket, 140mm post mount, 9 x 135mm quick-release|
|Fork||BMC Twostroke AL 20” lightweight aluminium with powder coat finish, 140mm post mount, 9 x 100mm quick-release|
|Stem||BMC aluminium, 40mm length, +/- 6° angle|
|Handlebar||SDG Slater, 650mm wide, 20mm rise, 19mm bar ends, 31.8mm clamp|
|Front Brake||TEKTRO HD-M286 hydraulic disc, 140mm rotor|
|Rear Brake||TEKTRO HD-M286 hydraulic disc, 140mm rotor|
|Brake Levers||TEKTRO HD-M286 hydraulic with short reach levers|
|Rear Derailleur||SRAM X4, medium cage, 8-speed|
|Shift Levers||SRAM X4 Trigger, 8-speed|
|Cassette||SunRace, 11-34T, 8-speed|
|Crankset||BMC lightweight forged alloy cranks 32T 1x specific narrow wide chainring|
|Front Wheel||Rim - DD32 20”, tubeless-ready, Hub - BMC CNC machined alloy hub body, sealed bearings, quick-release|
|Rear Wheel||Rim - DD32 20”, tubeless-ready, Hub - BMC CNC machined alloy hub body, sealed bearings, quick-release|
|Front Tyre||Kenda Booster 20”x2.4”, tubeless-ready|
|Rear Tyre||Kenda Booster 20”x2.4”, tubeless-ready|
|Saddle||SDG Fly Jr|
|Seatpost||BMC Alloy, 27.2mm|
|Pedals||Available to be purchased separately|
Built, Checked, Tuned and Tested
All our bikes are fully built, checked, tuned and tested by our Cytech qualified mechanics and then securely packaged, ready for delivery. All you have to do is add the pedals (if included), attach the handlebars to the stem and tighten them following the included detailed instructions or by watching our video and using the provided FREE tools. Visit our Bike Assembly page to see how you assemble your new bike once you receive it.
All bikes collected from our shop, are built, tested and ready to ride.
Please note, occasionally, manufacturers may change the specification without notice. Bicycles do not come with pedals unless otherwise specified. Bikes ordered for delivery will not arrive with the pedals installed, please refer to the owners manual and pedal installation guides provided for guidance. We do not install accessories to bikes, including mudguards. Bikes ordered for delivery that have tubeless compatible tyres and rims will arrive with inner tubes installed or with tubeless valves installed, this will be brand dependent. Sealant is available to be purchased separately.
If you require any assistance please contact our Customer Care team.