Bumping ride when drive slow

Hi all,

So I've had my car a few months now and the car feels bumpy when I drive slow, even on brand new, just laid, flat tarmac. I can only describe it as driving with one wheel like an egg almost. Took it to a garage they said I had a broken spring, after seeing the price for a genuine Renault 197 spring I decided to get the car lowered instead on H&R lowering springs. Only problem is that the bumpy ride is still there. If I drive over 30 i can't feel it but coasting at like 5-10 mph is when it's worst. Any ideas at all guys and girls as to what this might be?
 
strange one..never heard..i'd suggest the wheel bearing but it would be there regardless how fast you are going..
 
Yeah I'm confused by it. Got new rear discs (which include bearings) pads and a caliper. Tyres are all nearly new???
 
Oh forgot to say, I knocked the rear wheel on a curb going round a tight corner (railway bridge) maybe I broke something on that side? Had new rear pads, discs (which Inc wheel bearing) and caliper on that side.
 
Update:
Found out today that both inner tie rods and track rod ends have play in them, probably that then! They said everything else is solid and no wheels are buckled.