Your variegated leafed plant may have been grafted onto the trunk of a regular maple or it may be a reversion to the unvariegated kind. Regardless, the green leafed limbs will be more vigorous and will need to be all pruned out ASAP or they will totally take over the tree.

Thankyou so much for your reply nhbabs, so far this spring only one branch has the variegated leaves on it, will the tree survive if I cut off all the green leafed limbs?

A friend pruned it last year and I think he messed up something because these new strong green leafed ones have come from nowhere. :(

Oh well I did it ...Eeeps!!
I now have an Ornamental Stick lol but at least it looks healthy.

He seems to have pruned off every branch that he should have left and left all the ones he should have cut, thank goodness he didn`t take that centre one too.

Hopefully it will recover & not look silly for too long :)

I doubt you are going to happy with this tree going forward. It is NOT going to look any significantly better than it does now - it could very well die and/or the non-variegated growth could also come back just as strong as it was.

It is hard to see clearly exactly what kind of maple you started out with but it looks a lot like a variegated box elder, Acer negundo. These are not typically grafted so not sure what's going on there. But a couple of things to consider......box elders get BIG (30'x20') and attempting to keep one significantly smaller can cause problems. Like the stress displayed when the rootstock overtakes the scion. They also get some unpleasant insect infestations. And maybe the most important - your specific little tree now looks hideous (through no fault of your own) and is unlikely to improve its appearance much.

Get rid of it and start over with something more appropriately scaled. if you like the coloration of the foliage of this tree, maybe something like the dappled Japanese willow on a standard (Salix integra 'Hakuro Nishiki')?