I am slowly going through the old posts and there was a old post about the Pingle petcocks. Even though Pingle does not list one with the reserve for our "vintage" A/O GSXR's all Pingles have the same thread size. Just order the adapter only and then a two outlet w/reserve petcock. I have been using one for years on my 88 7-11. with the 38RS flatslides I still only get 10-12 mpg but whocares! Also as the adapter is offset you can grind out the center hole in your tank and turn the adapter around to get the petcock farther away from the LH head oil feed tube, before I did this the lever would get reel hot becaues it would touch if I opened the valve all the way.