OnGuard 8019E Mastiff e-Bike Titanium Chain Lock with X4P U-Lock is built for riders who need serious bike security without compromise. Designed specifically for high-value e-bikes, this heavy-duty chain lock and U-lock combo helps you secure your bike confidently whether commuting, travelling or parking in public areas.

This OnGuard e-bike chain lock shines when standard locks simply are not enough. The long 110cm chain makes it easier to lock around posts, racks or awkward urban infrastructure, while the included X4P U-lock gives you flexibility to secure wheels, frames or even use it separately as a compact disc lock.

Who is this chain lock for?

Ideal for riders who own e-bikes, cargo bikes, commuter bikes or expensive setups that spend time locked in public spaces. It suits commuters parking daily at work, riders leaving bikes outside cafés or shops, and anyone who wants a high-security bicycle lock designed to slow thieves down and encourage them to move on.

Who is this not for?

This is not the right choice if you want something lightweight to carry in a jersey pocket or for quick café stops only. At over 3kg, it prioritises maximum security over portability, so casual recreational riders or weight-focused cyclists may prefer a lighter lock option.

Why we love it

We’ve found combination lock systems like this simply make more sense for e-bikes. The chain gives reach and versatility, while the U-lock adds serious resistance where thieves usually attack. Our favourite part is the flexibility. You can secure multiple parts of the bike or split the locks depending on the situation.

Hot tip!

When locking an e-bike, try to secure both the frame and rear wheel to a fixed object using the chain, then add the U-lock through the main triangle or front wheel. Two different lock styles often make thieves look elsewhere.

Item specs

• Brand: OnGuard
• Model: 8019E Mastiff e-Bike Series
• Product type: e-bike chain lock with U-lock
• Chain length: 110cm
• Chain thickness: 10mm hexagonal links
• Shackle diameter: 14mm hardened steel
• Locking system: X4P Quattro Bolt locking mechanism
• Chain material: Titanium reinforced hardened steel
• Protective coating: Fully coated chain and lock body
• Cylinder: Bump-resistant locking cylinder
• Keys included: 5 laser-cut keys
• Additional feature: Lock reminder cable
• Use options: Chain lock + U-lock together or U-lock used separately as disc lock
• Weight: 3.26kg
• Compatibility: e-bikes, commuter bikes, cargo bikes, high-value bicycles