"the stock speedometer on just about every moped is 3-5mph optomistic. Gps 4 lyf"
agreed, thus the term moped miles per hour has been coined.
also i still don't see the point in a head temp guage unless you specifically know what temp you are aiming for, no one has posted an answer for that, i guess the best way would be to attach atemp guage to a bike that was really fast and reliable and see what numbers it produces, but then again does that change if you are using a different cylinder head aluminum vs cast iron etc. too many variables? maybe not.