Stock risers for a SB are 2", I put on 3.5" that a friend had given me and am a fan of the height/position. If you sat on one and it felt right, go with 2".

 

Everybody is built different and likes different riding positions. Before you start spending money on risers (and maybe cables) that you're not sure about, why not just install the bars on the stock clamps and ride it for a while. I think that will give you a better idea of how much higher you want to go (if any) and if you need more pullback.

 

Thanks for all your reply's. Much appreciated.