my grandad uses them all the time, i just use a ruler, tho i didn't need to take the head off my gpx when i had it, they are pretty expencive aint they
LOL you so funny mad man the number one rule is don't call me with sizes if you or your customer has used a ruler! i hate that!!!!
it's no were near accurate.
a bore/pistons go up in .25 of a mm you carn't do that with a ruler!