just put new pads in and there doesnt seam to be enough room, WHY????

Pistons need pushing back into their bores? You could try that first.

If they wont go all the way back you probably have a wee bit of air in the sytem if the callipers are fine then you may have to file down the opads a wee bit

Very unlikely to be air unless yo have a spongy lever – the most likely is either poorly made aftermarket pads that are too thick or too much fluid in the system preventing the pistons from being pushed right back – open the bleed valve then try to push the pistons back – fluid will come out.

spot on Tandem to much fluid in the system! cheers