Kryptonite Kryptolok Standard Bike U-Lock with 4-Foot Flex Cable
Kryptonite's mid-tier U-lock pairs a 12.7 mm hardened steel shackle with a 4-foot, 10 mm braided flex cable, so the U goes through the frame and rack post while the cable loops the wheels. It ships with a FlexFrame bracket that mounts to the bike tube, two stainless keys you can register for a replacement, an anti-rotation double-locking mechanism, and a sliding dust cover over a disc-style cylinder that keeps grit out of the keyway. Kryptonite rates it 6 out of 10 on its own security scale, and it weighs 3.65 lbs.
Check Latest Price on Amazon →Why You Need This
A cable lock feels like security until you read how fast a cutter goes through one. The Kryptolok solves the two most common theft shortcuts at once: the 12.7 mm hardened shackle resists the bolt cutters that defeat cable locks, and the included 4-foot flex cable reaches both wheels so nobody walks off with an unlocked wheel while the frame stays put.
🏆 How It Compares
Kryptonite's own line makes the trade-off clear: this Kryptolok sits at 6/10 security, above the lighter Keeper at 5/10 but below the Evolution at 4/10-rated keyed utility and well under the 16 mm New York Standard at 9/10. That makes it the value pick for bikes parked at a trailhead for a few hours — heavier and pricier than a cable lock, but with a shackle thickness that actually requires a tool to defeat, plus a cable that covers the wheels a U-lock alone cannot reach.
Pros & Cons
✅ Pros
- 12.7 mm hardened shackle blocks the bolt cutters that walk through thin cable locks
- 4-foot 10 mm cable lets you lock frame, wheels, and a hitch rack post with one piece of gear
- FlexFrame bracket mounts to the bike so the lock rides along instead of living in a pack
- Anti-rotation double-locking mechanism and sliding keyway dust cover
❌ Cons
- 3.65 lbs is real weight to carry on a long ride
- FlexFrame bracket is bulky and does not fit every frame — some riders end up carrying the lock instead
- The U shackle separates completely from its base when unlocked, which is easy to fumble with cold hands
🎯 Who Is This For?
Ready to Buy?
Check the latest price and availability on Amazon. Prices are accurate as of the date listed and may change over time.
Check Latest Price on Amazon →Compare with Alternatives
Frequently Asked Questions
What is the Kryptonite Kryptolok Standard Bike U-Lock with 4-Foot Flex Cable best for?
Families and weekend riders who need one lock that covers the frame, both wheels, and the hitch rack post when bikes are parked at a trailhead or campground
Who should buy the Kryptonite Kryptolok Standard Bike U-Lock with 4-Foot Flex Cable?
Campers who leave bikes locked on a hitch rack overnight and want the wheels covered too, not just the frame Riders upgrading from a thin cable lock after reading one too many 'cut in seconds' reviews Anyone who wants the lock to ride on the bike — the FlexFrame bracket means no pack space lost Buyers who want Kryptonite build quality without stepping up to the 16 mm New York-series price
What problem does the Kryptonite Kryptolok Standard Bike U-Lock with 4-Foot Flex Cable solve?
A cable lock feels like security until you read how fast a cutter goes through one. The Kryptolok solves the two most common theft shortcuts at once: the 12.7 mm hardened shackle resists the bolt cutters that defeat cable locks, and the included 4-foot flex cable reaches both wheels so nobody walks off with an unlocked wheel while the frame stays put.
What are the drawbacks of the Kryptonite Kryptolok Standard Bike U-Lock with 4-Foot Flex Cable?
Owners and reviewers call out a few trade-offs: 3.65 lbs is real weight to carry on a long ride FlexFrame bracket is bulky and does not fit every frame — some riders end up carrying the lock instead The U shackle separates completely from its base when unlocked, which is easy to fumble with cold hands
How much does the Kryptonite Kryptolok Standard Bike U-Lock with 4-Foot Flex Cable cost?
It is listed at $66.58 on Amazon. Prices on Amazon move around, so check the current price before you buy.
What do owners say about the Kryptonite Kryptolok Standard Bike U-Lock with 4-Foot Flex Cable?
It carries a 4.6-out-of-5 rating from 6,019 Amazon customer reviews.
Have a question we did not answer? The Amazon listing carries the full spec sheet and customer Q&A.
📖 Keep Reading: Cycling Gear Guides
Field-tested buying advice, comparisons, and setup tips from our guides — useful before you commit.
- Best Hitch Bike Rack 2026
Best hitch bike rack 2026: Thule Epos vs Kuat vs Yakima vs Allen for 2 bikes — receiver size, class ratings, e-bike weight limits, RV mounting.
- Bike Camping Gear Essentials
Build a reliable bike camping kit for 2026: gloves, pump, multi-tool and bike rack essentials for trail rides, overnights and family campground trips.
- E-Bike Hitch Rack Guide 2026
E-bikes weigh 40-70 lb, so most hitch racks cannot carry one. Per-bike ratings, hitch classes, and the racks that actually fit an e-bike.
- Bike Touring Repair Kit Checklist
Build a bike touring repair kit for 2026: multi-tool, pump, gloves and rack picks for multi-day rides, plus a roadside-fix playbook.
- Kuat vs Thule vs Yakima
Kuat, Thule, or Yakima? We compare the three big hitch bike rack brands model by model: weight limits, receiver fit, tilt and value for 2026.