Instructions kind of suck with the Yosh box, buuttt---each individual fuel map is 3 maps in one! Each map includes a baseline (ideal) map for the Yosh system they were testing and a +5% map and a -5% map. You can easily program which of the 3 maps is the default map. Soo---with the 3-way switch option 9 total maps are available. Only 3 map choices at a time, but with a computer handy the defaults can be quickly changed. Something like this, switch position one; map A or A+5% or A-5%, switch position two; map B or B+5% or B-5% and so on. Or, the switch could be used for one map and its +/- counterparts. Say switch position one; map A-5% for thrifty riding, switch position two; map A for racing, switch position three; map A+5% racing plus nitrous. The unit comes with 6 maps, one, a zero map doesn't count. That leaves 5 individual maps, each one with its +5% and -5% counterpart. Since no timing maps are shipped with the unit I don't know yet for sure if the same benefit exits. I think that it does because the software lists fuel map 1, timing map 1, fuel map 2, timing map 2 etc. To program the 3-way switch requires yet another button. To test this theory I printed out all 6 maps, each fuel map, baseline and +/- included a timing map! Now I guess I've just got to plug in some figures on the timing maps and go with them.