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Secondary Security Solutions A reliable secondary lock adds a vital layer of protection to keep your bicycle safe.
Real Life Opening
You pull up to the rack, running five minutes late for your meeting. You have your main lock, but you worry about your wheels or accessories being vulnerable while you’re away.
Finding the right best secondary bike lock helps you secure extra parts or adds a deterrent that makes thieves move on. These options provide added security when you need to leave your bike in public.
1. ABUS Frame Lock Mortise Chain
Best for: Owners of compatible ABUS frame locks.
This chain is designed to plug directly into an existing ABUS frame lock. It features a 6 mm thick square chain made from hardened steel.
You simply insert the bolt into your frame lock housing, meaning you don’t need an extra key to secure it. The plastic coating keeps your bike frame free from scratches or paint damage.
Pros
- Plugs into existing frame lock
- No extra key required
- Hardened steel square chain
- Includes plastic scratch protection
Cons
- Only fits specific models
- Limited 85 cm length
Why this one: This is the choice for anyone already using an ABUS frame lock system. It’s simple to use because it shares a key with your primary lock. If you don’t own a compatible ABUS frame lock, this chain won’t work for your setup.
2. Kryptonite KryptoFlex 525 Double Loop 2.5 FT Braided Steel Security
Best for: Securing accessories or multiple items quickly.
This is a 5 mm braided steel cable designed for cut resistance. It comes with double loops, allowing it to work with your existing U-locks or padlocks.
The vinyl coating prevents scratches on your equipment. Kryptonite provides a limited lifetime warranty for this product, which covers issues with the cable.
Pros
- Lightweight braided steel design
- Double loop for flexibility
- Vinyl coating prevents scratches
- Limited lifetime warranty included
Cons
- Thin 5 mm cable
- Requires separate primary lock
Why this one: This is a great, portable choice for securing a helmet or front wheel to your main lock. It isn’t a replacement for a heavy-duty primary lock, so avoid using it as your only security measure.
3. Kryptonite KryptoFlex 710
Best for: Locking multiple bikes or large items together.
This cable offers a 7-foot reach with a 10 mm thick braided steel core. It’s built to provide increased cut resistance for securing several items at once.
The double-looped ends make it compatible with any U-lock or disc lock you already own. A vinyl cover protects your bike’s finish from wear and tear.
Pros
- Long 7-foot reach
- Thick 10 mm steel
- Works with any lock
- Durable vinyl cover
Cons
- Heavier than shorter cables
- Needs secondary locking mechanism
Why this one: Choose this if you need to lock two or more bikes together. It’s very versatile, but its size makes it bulky to carry if you’re only securing one bike.
4. Master Lock Black Hardened Steel Link Folding Bike Lock
Best for: Riders who need compact, frame-mounted storage.
This lock uses hardened steel links to resist cutting and sawing. It includes a Velcro-strapped bracket that attaches to your bike frame for easy carrying.
The links are held together by stainless steel rivets designed to resist prying. A vinyl-covered body helps protect your bike from weather and scratches.
Pros
- Hardened steel folding links
- Includes frame-mount bracket
- Resists prying and cutting
- Compact storage design
Cons
- Shorter reach than cables
Why this one: This is ideal for commuters who want a lock that stays attached to the bike frame. If you prefer the long reach of a flexible cable, this folding design might feel too restrictive.
5. Kryptonite Parkview Folding Bike Lock
Best for: Short-term stops in lower risk areas.
This folding lock features 3 mm hardened steel bars and tight rivets. It weighs just 2.15 lbs, making it easy to carry in a pocket or on the frame.
It comes with a mounting bracket for your bike. You get two keys, and it provides 2.9 feet of usable length for locking to fixed objects.
Pros
- Lightweight and portable
- Includes mounting bracket
- 2.9 feet of length
- Two keys provided
Cons
- Best for short-term use
- 3 mm steel bars
Why this one: This is a solid choice for someone who wants to avoid carrying a heavy chain. It isn’t intended for long-term storage in high-theft areas, so look for a heavier chain if you leave your bike for hours.
6. Kryptonite Parkview Chain Bike Lock
Best for: Heavy-duty, everyday protection.
This chain uses 8 mm hardened steel links to stop hand tools and bolt cutters. It extends to 3 feet and includes a nylon sleeve to prevent scratching.
It comes with two stainless steel keys. Kryptonite offers a limited lifetime warranty for this lock, ensuring long-term support.
Pros
- 8 mm hardened steel
- Durable nylon sleeve
- 3-foot length
- Lifetime warranty
Cons
- Heavier than cable locks
- Requires carrying space
Why this one: If you want a robust physical barrier that’s harder to cut than a cable, this is your pick. It’s significantly heavier than the other options, so ensure you have a way to carry it.
7. Master Lock 6 ft Cable Bike Lock 4-Digit Combination 1/2
Best for: Keyless convenience and simple daily use.
This 6-foot cable uses a resettable 4-digit combination. The 1/2 inch diameter braided steel provides a basic theft deterrent for everyday needs.
The vinyl coating protects your bike from scratches. It’s designed to be portable and flexible for reaching around racks or poles.
Pros
- No keys to carry
- Resettable 4-digit code
- 6-foot long cable
- Vinyl scratch protection
Cons
- Basic security level
- Combination can be forgotten
Why this one: This is perfect for someone who hates carrying keys and only needs a basic deterrent. It isn’t the most secure option for high-risk areas, so use it carefully.
8. Amazon Basics Weather Resistant Bike Security Cable Lock
Best for: Weather resistance.
This cable is 70 inches long and 8 mm thick. It features a weather-resistant plastic coating to keep the steel safe from the elements.
The lock mechanism is easy to use and doesn’t require a key to lock. It includes a spare key for opening the device, ensuring you have a backup if one is misplaced.
Pros
- Weather-resistant coating
- 70-inch length
- Easy lock mechanism
- Comes with a primary key and a backup.
Cons
- 8 mm diameter
- No mounting bracket
Why this one: This is a simple, no-frills cable for basic security. It provides basic security for casual use.
9. Bike Lock Cable Pair
Best for: Multi-purpose accessory security.
These two 15-inch cable locks are made from high-quality alloy with a protective plastic coating. They’re lightweight and bend easily.
Each lock comes with its own set of keys. They’re useful for securing helmets, gym lockers, or garden gear.
Pros
- Comes as a pair
- Lightweight and flexible
- Rust protection coating
- Wide variety of uses
Cons
- Short 15-inch length
- Different keys for each
Why this one: This is a great set for securing loose items like helmets or seats. Don’t rely on these short cables to lock your entire bike frame to a rack.
How to Choose Yours
Think about your daily routine and where you leave your bike. Choose a lock that balances the level of security you need with how much weight you’re willing to carry.
- Do you need to secure your bike to a rack or just lock a wheel?
- Will you be leaving your bike in a busy area for a long time?
- Do you prefer using a key or a resettable combination code?
- How much room do you have to carry a heavy chain or folding lock?
- Do you need to lock multiple items, like a bike and a helmet, together?
- Is your bike frame sensitive to scratches from metal chains or cables?
For general safety, the Consumer Product Safety Commission provides guidance on product standards that help ensure items are built to last.
The Verdict for Most People
Most riders should choose the Kryptonite Parkview Chain for its balance of 8 mm hardened steel security and 3-foot length. It provides a strong physical deterrent that’s reliable for everyday use.
If you prefer to go keyless, the Master Lock Cable Lock is a flexible and convenient alternative. Consider your specific locking needs before you decide.
Frequently Asked Questions
How do I stop the lock from scratching my bike frame?
Most modern locks come with a protective sleeve or vinyl coating specifically designed to prevent paint damage. Ensure the sleeve is pulled over the metal links or cable before you secure it to your frame.
Is a secondary lock enough to keep my bike safe?
A secondary lock is meant to be an extra layer of protection, not a replacement for a high-quality primary lock. Always use it alongside a primary U-lock or heavy chain to secure your frame to a fixed object.
How do I mount a folding lock to my bike?
Most folding locks include a dedicated transport bracket that attaches to your frame using straps or screws. This allows you to carry the lock conveniently without it rattling or taking up space in your bag.
Do I really need to worry about weather resistance?
If you lock your bike outside regularly, a cover for the keyhole helps keep out debris and rain. Look for locks that include this feature to protect the internal mechanism.
What is the best way to secure a bike helmet?
A lightweight, flexible cable is the easiest way to secure a helmet to your bike frame. These cables are simple to thread through the helmet strap and your main lock, making them a popular choice for commuters.
A thicker cable provides increased cut resistance. While heavier to carry, the added thickness provides a better deterrent for your gear.
Final Thoughts
Choosing the right gear doesn’t have to be complicated, but it makes a world of difference for your peace of mind. Once you’ve picked your favorite, head over to your local bike shop to see how it fits your frame. You’ll feel much better knowing your ride is ready for anything.