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 FOUR 29" Mountain Bike 2022
The BMC Twostroke AL FOUR 29" Mountain Bike utilises a reactive, light and strong Premium grade, hydroformed aluminium frame and aggressive geometry to promise an enthusiastic ride experience over the most demanding XC-style trails. A SUNTOUR XCM 32 suspension fork is added to cushion the bumps, affording extra control and accuracy when the riding gets technical. Clearance for tyres of up to 58mm in width allows the bike to tame even the roughest tracks, and internal cable routing keeps the looks clean and professional.
The SRAM SX Eagle 1 x 12-speed gear set-up flicks through its vast range of ratios with precision to help the rider explore any terrain with an ideal cadence. Matching SRAM hydraulic disc brakes infuse confidence on even the fastest descents thanks to their easily modulated stopping power that's reliable in even the muddiest conditions. Robust 29" wheels complete the build and are shod with wide and grippy Vittoria tyres.
- A versatile, agile and confidence-inspiring hardtail suitable for all XC style trails
- Premium hydroformed aluminium frame with smooth welds is light and reactive
- The frame offers clearance for up to 58mm wide tyres
- Internal cable routing keeps the aesthetics clean and crisp
- Moulded covers on the chainstay, a chain suck plate and helicopter tape on the downtube protects the frame
- A SUNTOUR XCM 32 fork cushions the trails and increases control with its plush suspension
- A 67˚ head angle, long front-end and 75° seat angle helps the rider attack steep and loose terrain with perfect weight distribution
- Strong, reliable 29" wheels and wide, grippy Vittoria tyres tame any trail
- SRAM SX Eagle 1 x 12-speed gears are accurate and give a huge range of ratios for any terrain
- SRAM hydraulic disc brakes are precise and powerful
|Frame||BMC Twostroke AL Premium hydroformed, smoothwelded aluminium, internal cable routing, BSA threaded bottom bracket, post mount disc attachment|
|Fork||SUNTOUR XCM 32, 100mm travel|
|Stem||BMC Forged 6061 Alloy|
|Handlebar||BMC Alloy, 760mm width|
|Front Brake||SRAM Level hydraulic disc with SRAM Centerline rotors (160mm on S-M sizes, 180mm on L-XL sizes)|
|Rear Brake||SRAM Level hydraulic disc with SRAM Centerline rotors (160mm on all sizes)|
|Brake Levers||SRAM Level hydraulic|
|Rear Derailleur||SRAM SX Eagle, 12-speed|
|Shift Levers||SRAM SX Eagle, 12-speed|
|Chain||SRAM SX Eagle, 12-speed|
|Cassette||SRAM SX Eagle, 10-50T, 12-speed|
|Crankset||SRAM SX Eagle, 30T chainring|
|Front Wheel||Rim - XCD23 29”, tubeless-ready, Hub - Shimano MT400|
|Rear Wheel||Rim - XCD23 29”, tubeless-ready, Hub - Shimano MT410|
|Front Tyre||Vittoria Barzo 29” x 2.25”, tubeless-ready|
|Rear Tyre||Vittoria Barzo 29” x 2.25”, tubeless-ready|
|Saddle||Selle Royal Seta|
|Seatpost||BMC Alloy, 31.6mm, 0mm offset|
|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.