Well trying to get more speed on top end is becoming an issue trying to find right sprocket. I am trying to find a "C" type sprocket that has either 12 or 14t with 5/8 bore that will fit #40 chain is impossible to find! So..instead could i use a "B" type sprocket which i can find easily... but will i have issues with it lining up right or could i use washers, spacers or locking collar to make up the difference of it only having one shoulder? Or should i be satisfied with the 35mph its reaching now. Any or all suggestions appreciated.