Ram air compensation

so a number of bikes I tune have ram air compensation maps that are rpm x gear based,how would I go about tuning these maps, is this more beneficial on a dyno or the street?

This isn't something you're typically going to be able to optimise on the dyno as it's all but impossible to replicate the ram air effect as it really only comes into play at higher speeds. The technique I'd use is to log the air fuel ratio at low speed vs high speed and you see a trend for the air fuel ratio moving lean at higher speed then you can account for this in the maps you have - The speed understandably is relative to gear and hence you can make adjustments in the appropriate gear map. You are likely to find that unless you're making substantial changes to the engine's mechanical design that the base maps from the manufacturer for the ram air affect are likely to be quite close anyway.