How to tell if Head mod has already been done?
 

Anyone know if there is a way to tell if the RB head mod has been done on a head by looking at it? measurement?

Thanks

Calculate the trapped volume
Measure the squish
CC the combustion chamber

Here is some more info.

http://www.gasgasrider.org/html/measuring_squish.html

Measuring the squish is probably the easiest place to start

Thanks, Guess I'll have to pop the head and measure it.

Easy way is the squish. If it says ~2mm then it hasn't been touched. If its 1mm then it likely has.

If you pop it & there is the black anodising all over then it hasn't been touched.

If it has been modified you can't tell who by, but have a check of some of the old threads & they'll give you a clue as to what they look like when done.

this is my thread, first pica are skimmed but they look black all over the inside to start with.
http://www.gasgasrider.org/forum/showthread.php?t=16560