Bouncing Brakes??

[brainbug007]

I'm hoping someone can shed some light on this one.. The haynes manual for my motorbike said I should replace most of the braking elements after 2 years which I've done. So I put new pads, discs, lines & fluid in. Now when I brake it's a bit weird and hard to describe. At speed it seems ok but as I slow down (like when approaching a red light) and my speed gets down below say 10/15 mph, the front brake doesn't seem to work properly and the front of the brake bounces up & down on the forks so to speak as it finishes slowing down and the rate of deceleration doesn't seem very good. I'm wondering is this just something like the disc & pads wearing in? Or perhaps is this what people refer to as spongy brakes and there's air in the brake line?