Sportneer Bike Lock: Heavy Duty Anti Theft Bike U Lock with 5ft Security Steel Cable - 17mm Shackle Bicycle U-Locks with 2 Keys & Mounting Bracket for Road Mountain Bike, Size 7.76''x5.02'', 1.64lb

Why it's worth it

A 17mm hardened shackle paired with a five-foot cable, which is enough to cover the frame and both wheels at a normal street rack. It weighs about a pound and a half, and that weight is the whole point.

Shackle thickness is the lock spec that actually matters, and this one has it. The shackle measures 17mm across, thick enough that bolt cutters won't close on it. A thief needs an angle grinder and the nerve to use one in public. Sportneer rates the body against 12 tons of hydraulic shear, which you should read as a manufacturer figure — but the diameter is real, and you can measure it yourself.

The included cable is what makes it work on an e-bike specifically. Loop it through the front wheel and your rack, then close the U around the frame and a solid post. Your wheels stay with the bike. That matters more here than on a pedal bike, because a quick-release wheel and a rack full of accessories are the easy things for someone to walk off with.

From our review of 8 e-bike accessories, by David Sinclair, Managing Editor

What we like

• +Shackle thickness is the lock spec that actually matters, and this one has it
• +The included cable is what makes it work on an e-bike specifically
• +A frame bracket comes in the box and clamps onto tubes between roughly 26 and 38mm, so the lock rides on the bike instead of…

What to know

• –It's heavy, it's bulky, and the U isn't especially big
• –And a lock is only as good as the thing you attach it to