How to Use a Kryptonite Bike Lock (U-Lock, Cable, Bracket and Keys)
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Kryptonite locks are simple to use, but a few setup steps make a big difference if you ever lose a key. This guide covers what to do when you unbox the lock, how Kryptonite recommends locking up, and how to look after it.
Table of Contents
Step 1: Record and Register Your Key Number
Before you do anything else, find your key number. According to Kryptonite’s support page, it’s usually one or two letters (the key prefix) followed by 4 to 6 numbers, stamped on the key. Some New York models have it on a metal tag on the key ring. It’s not on the lock or the packaging.
Write it down and store it somewhere safe, and register it on Kryptonite’s key registration page. Kryptonite notes that registering your keys doesn’t automatically sign you up for its anti-theft protection offer, which you register for separately if your lock includes it.
Step 2: Mount the Bracket (Optional)
Most Kryptonite U-locks come with a FlexFrame-U bracket. Kryptonite’s support center has a bracket installation guide with a video and written instructions. Mount it where it won’t hit your legs or bottle cage. If the lock rattles or doesn’t fit your frame, carry it in a bag or on a rear rack instead.
Step 3: Open and Close the U-Lock
- Insert the key and turn it to release the shackle.
- Pull the shackle out of the crossbar.
- Place the shackle around your bike and a solid object.
- Push the crossbar back onto the shackle until both ends latch.
- Turn the key back if your model requires it, remove the key, and tug to check.
Step 4: Lock Up the Kryptonite Way
Kryptonite’s bicycle lock-up guide gives these tips:
- Lock to a solid object the bike can’t be lifted over, and that can’t be cut.
- Choose a well-lit area with high foot traffic.
- Lock according to value: frame first, then the back wheel, then the front wheel.
- Get a tight fit. The less room inside the U-lock or chain, the harder it is to use tools.
- Keep the lock off the ground with the keyhole facing down.
For a full walkthrough, see how to properly lock a bike.
Step 5: Use the Included Cable
Many Kryptonite U-locks, like the KryptoLok Standard and Evolution Mini-7, come with a 4-foot flex cable. Thread it through your front wheel, then slip both looped ends over the U-lock shackle before you close it.
- BUILT TO LAST: The Kryptonite Kryptolok Standard U‑Lock is constructed with a 12.7mm hardened performance steel shackle to help resist cutting and leverage attacks, while a durable vinyl‑coated protective sleeve prevents scratches to your bike’s frame and preserves its finish
- DOUBLE-DEADBOLT DESIGN: Locks the shackle on both sides of the crossbar for enhanced holding power and resistance against twisting and pulling. Certified by Sold Secure Silver, it also includes a high‑security disc‑style cylinder to resist picking and drilling
- VERSATILE SECURITY WITH 4‑FT CABLE: Includes a heavy-duty 10mm x 4‑ft (120 cm) double‑loop security cable ideal for securing your front wheel, helmet, or accessories. Together with the U‑lock, it is perfect for securing bicycles and e‑bikes at work, school, or around town
- STANDARD, COMMUTER-FRIENDLY SIZE: This U-lock features interior locking dimensions of 4” x 9” (10.2cm x 22.9cm) and a total lock weight of approximately 3.65 lbs (1.66 kg), providing a versatile locking reach for thicker poles and racks. Weather-reated components help protect against rust and outdoor exposure for reliable everyday use
- EASY MOUNTING BRACKET INCLUDED: Comes with a secure FlexFrame‑U bracket that attaches directly to your bike frame for hassle‑free transport—allowing you to carry the lock easily with no backpack or lock bag required
Step 6: Look After the Lock
Kryptonite’s maintenance guide suggests lubricating the keyway, shackle tips and locking areas about every two months, more often in rain, snow or salt. It recommends a dry lube and warns that standard WD-40 is a solvent, not a lubricant.
Which Kryptonite Lock Do You Have?
| Series | Security level | Example |
|---|---|---|
| KryptoLok | Everyday | KryptoLok Standard, about $80 |
| Evolution | Mid to high | Evolution Mini-7, about $105 |
| New York | Highest | New York Standard, about $146 |
- BUILT TO LAST: The Kryptonite Evolution Mini‑7 U‑Lock is constructed with a 13mm hardened Max‑Performance steel shackle to help resist cutting and leverage attacks, while a durable vinyl‑coated protective sleeve prevents scratches to your bike’s frame and preserves its finish.
- DOUBLE-DEADBOLT DESIGN: Locks the shackle on both sides of the crossbar for enhanced resistance against twisting and pulling. Certified by Sold Secure Gold, it also includes a high‑security disc‑style cylinder to resist picking and drilling
- VERSATILE SECURITY WITH 4‑FT CABLE: Includes a 4‑ft (120 cm) double‑loop security cable ideal for securing your front wheel, helmet, or accessories. Together with the U‑lock, it is perfect for securing bicycles and e‑bikes at work, school, or around town
- COMPACT, COMMUTER-FRIENDLY SIZE: This U-lock features interior locking dimensions of 3.25” x 7” (8.3cm x 17.8cm) and a total lock weight of 3.55 lbs (1.61 kg), providing a tight fit around bike racks to deter leverage attacks. Weather-treated components help protect against rust and outdoor exposure for reliable everyday use
- EASY MOUNTING BRACKET INCLUDED: Comes with a secure FlexFrame‑U bracket that attaches directly to your bike frame for hassle‑free transport—allowing you to carry the lock easily with no backpack or lock bag required
Shopping for a new one? See our best bike locks and heavy duty bike locks guides.
FAQ
Where is the key number on a Kryptonite lock?
It’s stamped on the key, or on a metal tag on the key ring for some New York models. It isn’t on the lock or packaging.
How do I attach the Kryptonite cable to the U-lock?
Run the cable through your front wheel and slide both looped ends onto the shackle before closing the lock.
Do I need to register my Kryptonite lock?
It’s strongly recommended. Registering your key number makes ordering replacement keys much easier.
