300/440/550 Crankshaft bearings

[lego]

Hey all!

I've torn down my js550 for a rebuild... Got down to the crank and noticed that the crank bearings have an outer O-ring around them.
What do they do?? Is there any point to them? What would happen if they were replaced with bearings without the ring?

 

[lego]

Any one?

 

[WFO Speedracer]

The orings keep the bearings locked in place in the crankcase, you can use regular bearings and put a thin pink film of red loctite on the bearings to hold them in position in the cases