NS Bikes Define AL 170 2 Mountain Bike 2025 - Downhill Full Suspension MTB

Built to dominate technical descents while still handling climbs, the Define AL 170 2 is NS Bikes’ biggest model in the Define range. It features a mixed-wheel setup – a fast-rolling 29” front and compact 27.5” rear – for stability, agility, and a balanced ride on rough terrain. This bike is equipped with Rock Shox suspension, Shimano drivetrain and brakes, and tough alloy construction, making it ready for the challenges of enduro and downhill trails.
Key Features
- Aluminium frame with 170mm rear travel, AL6061-T6 + AL6066-T6, custom hydroformed
- Rock Shox ZEB Base fork with 180mm travel, Boost spacing
- Marzocchi Bomber CR rear shock, Trunnion mounted, 170mm travel
- Shimano Deore M6100 12-speed drivetrain for precise shifting
- Shimano MT410 brakes with 200mm rotors for reliable stopping power
- Mixed wheels: 29” front, 27.5” rear with Schwalbe Big Betty tyres
- Hidden external cable routing and big bearing pivots
- Available with 0% APR finance
With the Define AL 170 2, NS Bikes delivers a machine for riders who want downhill performance with the flexibility to climb back up. Its mixed-wheel setup combines a 29” front wheel, which powers over obstacles, with a smaller 27.5” rear wheel that allows for more suspension travel and a responsive feel in technical sections.
Built around a rugged AL6061-T6 + AL6066-T6 alloy frame, the Define AL 170’s geometry is aggressive and ready for rough terrain. Rock Shox’s ZEB Base fork offers 180mm of front travel, while the Marzocchi Bomber CR rear shock provides plush 170mm travel, keeping the bike balanced and controlled on descents. Shimano MT410 brakes with 200mm rotors give you stopping confidence, while the Deore 12-speed drivetrain ensures you have the right gear when climbing.
With hidden external cable routing and robust construction, the Define AL 170 2 is designed for demanding riders who want a reliable, capable bike that thrives on the most challenging trails.
Occasionally, without notice, manufacturers change product design and/or specifications.
Frame | NS Bikes Define AL w/ 170mm travel, AL6061-T6 + AL6066-T6, custom hydroformed tubes |
Fork | Rock Shox ZEB Base 180mm travel, 15x110mm Boost, 1.5 tapered steerer tube, 44mm offset |
Rear Shock | Marzocchi Bomber CR Trunnion 225x70, S-400, M-450, L-500 lbs/in |
Headset | GW integrated tapered IS42/IS52, sealed bearings |
Stem | NS Bikes Tone 45mm, 35 |
Bars | NS Bikes 35, 800mm, 20mm rise / NS Bikes Licence 35, 820mm, 35 mm rise |
Front Brake | Shimano MT410, 200mm |
Rear Brake | Shimano MT410, 200mm |
Rear Mech | Shimano Deore M6100, 12spd |
Shifters | Shimano Deore M6100, 12spd |
Speed | 12 |
Rims | Octane One Solar 29” front, Octane One Solar 27.5” rear, 32h, tubeless ready |
Front Hub | NS Bikes 110x15mm Boost (sealed bearings) |
Rear Hub | NS Bikes 148x12mm Boost (sealed bearings) |
Spokes | Spokes w/14mm nipples |
Front Tyre | Schwalbe Big Betty BikePark 29x2.4 |
Rear Tyre | SSchwalbe Big Betty BikePark 27.5x2.4 |
Seat Post | Kind shox rage i internal S-125, M-150, L-170mm, 31,6mm |
Saddle | WTB Volt Medium Steel SL |
Chainset | Shimano Deore FC-MT5101 170mm 34t |
Bottom Bracket | Shimano BSA 73mm |
Chain | Shimano Deore M6100, 12spd |
Cassette | Sunrace CSMZ800, 11-51t, 12spd |
NS Define Size Chart
Frame Size |
Rider Height (cm) |
Rider Height (in) |
S |
158 – 170 |
5'2" – 5'7" |
M |
168 – 179 |
5'6" – 5'11" |
L |
176 – 187 |
5'9" – 6'2" |
What size frame do I need if I am between sizes? - read here
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NS Bikes Define AL 170 2 Mountain Bike 2025 - Downhill Full Suspension MTB
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