Simple. Look at this link http://www.bikebandit.com/oem-parts/2007-suzuki-boulevard-s40-ls650/o/m147574#sch526807
Loosen the two nuts #39 and 40, then turn shaft #38 till the shifter is in the position you want. Tighten the two lock nuts and you're done.
Careful, one of those nuts is left handed thread.
Suzukisavage.com is awesome resource for S40 . Best upgrade you can do on that bike is fork brace. It makes bike handle much better. And you can put sportster seat on it if I remember correctly![]()