You need a U lock and likely two. Most of the cables are easy to cut.

We have two kids on a major urban university campus with 50,000 students in the middle of a major city. Bike theft is rampant on campus but we have found ways that seem to work. Bikes are outside 24/7.

1. We use the Sheldon Brown locking method.

2. We use Pitlocks, this set.

3. When the bike is locked to the rack overnight, we recommend using a second U lock to lock the front wheel to the frame (through the rim into the main frame triangle. This lock can be left in place at the rack to prevent having to carry it all over campus. All of our locks are keyed alike for the entire family. This lock for the lock that is used when the bike is out and about. This lock for overnight storage on campus and added to the out and about lock with the longer shackle.

If you use one lock and a 4' cable, then you will need to take the cable with you. While this is potentially easy to cut, the thief has to have two different sets of tools to steal the whole bike and is not likely to go looking for just a front wheel. They would need one set to defeat the cable (to just steal the wheel) or a different set to defeat the U lock.

4. If you can, then park your bike next to someone not so careful (not hard to do - most students are horrible about locking their bikes). They will pick their bike, not yours. This quote applies.

The Pitlocks are expensive, but they can be moved from bike to bike and they are a major discouragement to thieves.

Our kids both have really nice university bikes. They are circa 1985 road bikes of the day with custom built wheels etc... They are not worth a huge amount but they ride and hold up way better than department store bikes. That said, we have not had a single issue with any of the bikes but have routinely seen others stolen from right next to ours.

Don't scrimp on the U locks. The crummy ones are easily defeated.

J.