Bike U-Locks

Pick a U-lock that fits around your bike frame and the object you lock to with 1–3 inches of extra space; smaller clearances reduce leverage attacks but must accommodate both the frame and a wheel or use a separate cable for the second wheel

Look for hardened steel shackle, a robust crossbar and cylinder rated pick- and drill-resistant, and a lock design with minimal exposed shackle; higher security ratings or Sold Secure/ART certifications indicate stronger resistance to cutting and prying

U-lock prices commonly range from budget options under $50 to higher-security models over $100, with many well-rated choices around the mid-$50 to $80 range depending on materials, weight and lock quality

Most U-locks are sized to secure the frame and one wheel; to secure both wheels, use a second lock or pair a U-lock for the frame with a cable or secondary lock for the other wheel

Use a frame-mounted bracket, a mounting strap, or put the U-lock in a backpack or saddlebag; secure mounting reduces rattling and keeps the lock accessible when you stop

Keep the locking mechanism clean and lubricated with a dry graphite or silicone-based lubricant periodically, avoid leaving the lock exposed to corrosive environments for long periods, and check for wear or damage to the shackle and keyway

Lighter U-locks often use thinner shackles or lower-grade materials and may be easier to attack; look at construction, material hardness and security ratings rather than weight alone when assessing protection