dumb question, when to oil o-rings

Is there a rule of thumb? I was replaced the o-rings in my carbs a while ago and cannot remember if I pre-oiled them, any harm? And then I saw that it was recommended to pre-oil the o-ring to the tach drive. I know that it will seal better initially, but since it is in an oil environment, isn't the worst that could happen is it initially squirts a little oil (like a oil filter would?)

I've never oiled an oring in my life. Never had one leak after replacing either so I doubt it matters for the most part.

The main reason they say to pre-oil an oring is so it slides into postion easier. pre-oiling doesn't make it expand or anything, it just slides in easier. Kind of like some other things I know of... :laugh: :laugh:
Ride safe.

The Milkman is right .

On second thought , everyone it right .

If it does'nt leak , no harm done .

I use wheel bearing grease instead of oil myself.