Experiments with airbags on motorcycles were performed as early as the 1960s. However, they have never shown the promise that automotive airbags do, since the rider is not enclosed. The most effective motorcyclist protection has always been that which is attached to the rider. Recently, a few aftermarket rider-worn airbags have come to market, though there are concerns about unintended deployment (which could possibly cause an accident) and inflation speed, which must be extremely quick in order to make the airbag effective. Honda's airbag system seeks to reduce the speed at which the rider impacts the object he collides with or the road. It appears that the deployed airbag may also change the rider's trajectory, and it's unclear what issues may arise when a passenger is aboard. As with cars, the need to replace the airbag after a collision is likely to affect insurance rates.