Opus Bikes Size Chart The Spark aluminum adventure bike is designed to take you anyplace you want to explore. Through axles, disc brakes and generous tire clearance deliver comfort and control in all conditions. Meanwhile, the Spark's lower bottom bracket and longer stays give you greater stability for when the pavement ends and the fun begins. The Opus Spark. Whether it's a club ride or full-day epic, you can take it all in stride. Features: - Shimano 105 11-speed gruppo with FSA adventure crank - Shimano Flat Mount hydraulic disc brakes - Extra-wide 42-mm tire clearance - Frame: Meta 30 6061 aluminum - Fork: Full carbon tapered 1-1/4" to 1-1/8" - Shifters: Shimano RS-505 2 X 11 - Front derailleur: Shimano 105 - Rear derailleur: Shimano 105 - Brakes: Shimano RS-505 Flat Mount Hydraulic Disc - Brake levers: Shimano - Crank: FSA Omega Adventure - Chainrings: XXS-XS 46-30 S-XL 48-32 - Bottom bracket: FSA BB-4000 - Cassette: Shimano 11-28 - Chain: Shimano - Headset: FSA Orbit Integrated Sealed - Handlebar: X-Race Aero 16deg Flare - Stem: Opus Bronze - Grips/Tape: Velo Vexgel diamond grip - Saddle: Selle Italia Q-BIK - Seatpost: Opus Silver 27.2 X 300 - Wheels/Rims: Alex Boondocks 3 Tubeless Ready - Hubs: Alex through axle 12mm FR/RR - Tires: Vittoria Terreno Dry 700 X 33 - Pedals: N/A - KCNC through axles - FR/RR rack and fender mounts with hardware - Weight: 21.5 lbs