Swapped my factory 17" wrx wheels for some 18" numbers, since I've done this I'm getting a noise from n/s rear wheel like a shot wheel bearing noise, only noticeable from 40-70 then shuts up at 70, no play in wheels.
Would having to directional tyre on the n/s cause this , no spigot rings ? Bad balancing ? I'm totally stumped

 

If its only happened since you changed the wheels its more than likely going to be a distorted tyre, its probably got rises and flat spots on it, run your hand around the tyre you think it is with the palm of your hand spread the width of the tyre and run it back and forth you should be able to make them out, it can give the impression its a bearing

 

If this is the case is something to worry about ?

 

Depends really on the overall condition, if its showing age I.e cracks in between the tread then best to replace it as that is more than likely contributing to the noise your hearing, others that have had bad moulded tyres that make that noise have driven them until they are dead, my choice would be to change it, the noise would drive me insane alone

 

rotate the wheels front to back so see if the noise moves.

 

feathered tyre id emagine

 

The tyre does not look that bad 4-5 mm tread , looks like a slight deformaty on the inside wall tho