Tyre wear on outside edge

[swansea v6]

After replacing my front tyres around 6000miles ago they are wearing quite badly just on their outer edges.

I have ordered new tyres from camskill and when I get them fitted I will get a four wheel alignment carried out. What causes just the outer wear? Tyre pressure has never dropped (tho as they are non standard alloys I have had to play around with the pressures).

Could it be worn suspension parts??

[BIG DUNC]

Could be worn suspension parts, but before you worry, see what the aligment check does.
Most usual reason for wearing the outside edge is the tracking having too much toe in, which the alignment boys will sort for you easily.