OnGuard Bulldog Mini TC 5013TC

Although the OnGuard Bulldog Mini TC 5013TC isn't as strong or durable as U-locks in OnGuard's top-of-the-line Brute series, it is very lightweight and inexpensive. At just 2 pounds, the OnGuard Bulldog Mini TC 5013TC is highly portable and not too heavy to throw in a bag or backpack -- although a mounting bracket is included as well. The Bulldog Mini TC 5013TC bike lock gets excellent reviews from owners, especially those who were specifically looking for a lightweight and inexpensive lock. It has a 13 mm shackle and an interior size of approximately 3.5 inches by 5.5 inches. Reviewers say the small interior size is a good thing since it gives thieves less leverage to work with. This mini bicycle lock also comes in a longer size for beefier bike frames in the OnGuard Bulldog Mini TS 5013TC (*Est. $22), which has an interior size of 3.5 inches by 7 inches. The TS version gets high marks in an anti-theft test, where it resists hammers and chisels, although it does eventually succumb to power tools. If you live in a high-theft area, the OnGuard Brute STD 5001 (*Est. $40) is a better choice, and it has an industry-leading $5,000 anti-theft warranty. However, the anti-theft protection plans for all OnGuard locks are not available in New York.

There are fewer reviews available for the OnGuard Bulldog Mini TC 5013TC than several other popular bike locks, but we found a number of owner-written reviews on Buzzillions.com. In addition, a cyclist at TownsAndTrails.com writes a detailed review based on personal testing. BikeRadar.com also tests the OnGuard Bulldog Mini TS, which is slightly longer but otherwise identical.