If you’re chasing around for an Olympic Bar, you may hear people talk about bushes / bushings and bearings / linear bearings / needle bearings and wonder what they’re talking about.
In short, barbells with bearings have a smooth rotation so are better for olympic style lifts – they’re also more expensive. Barbells with bushings are cheaper, but have poorer rotation, which make them suitable for lower weights and most home gyms.
A little more detail
Bushes and bearings refer to the mechanism on which the ends of the bar spins. Huh? So for a 20kg bar, we create a 7ft bar at 28mm-32mm diameter. We create an outer steel sleeve that is slipped onto each end of the bar and either bolted on to the bar, or clipped on. The outer sleeve then spins around the inner sleeve creating a rotating end.
Left with just an outer sleeve and inner sleeve, the spin will be very poor, and the components will wear out very quickly as you have the outer steel sleeve rubbing directly on the inner bar creating too much friction. This is where the bushes and bearings come in – they sit between the bar and the sleeve, allowing the sleeve to spin more freely around the bar, reducing friction and wear.
Bushings tend to be brass, or bronze (the latter being a better quality as it self lubricated). Put simply, they fit between the bar and the sleeve either at just the inner edge, or inner and outer edges of the sleeves, reducing friction between the outer and inner sleeve, making the spinning movement smoother.