hi Gents, Can anybody enlighten me what range of spanner sizes I'll need for my 1200 sportster? I have a fair selection of metric sockets and spanners, but only odds and ends in imperial sizes.

I have NFI coz my collection is quite big, but I find it's best to wait until you need them, then buy the best one in that size that you can so it lasts a lifetime. 
When buying in bulk most of us try to save a buck and that usually costs more in the long run - either in time (fixing the fuckups poor tools create)  or re-buying worn/broken/crap tools again.

As funny as that is I don't go near nut fuckers anymore.

Just buy a basic Imperial Socket set and spanner/ring combo and allen key set.

You will need Torx bits for controls and taking rear guard off too.

Doesn't need to be a comprehensive set, most of it is 1/2 inch and 5/8th's with only the steering nut and front pulley nut the only oddball huge ones.

Oddly enough you also need a 10mm metric spanner for the battery nuts.

Thanks guys, some of those responses answered my question very well.