There's always a problem with motorbikes on Purdown; here we see a car making an effort to block motorbike/scooter access from the lower entry point, (Park Hill/Frenchay Park Road/Broomhill road roundabout), by blocking all wheeled access entirely.
Unfortunately, as a study on motorbiking in Manchester reports, you can't actually lock out motorbikes. All you do is block off legitimate access, while forcing the motorbikers to bring a circular saw, torch any wooden barriers, and drive a stolen car into any gate. Certainly someone had cut the padlocks at the Lockleaze end last month. Still, a heroic effort by this car to block access from the east.