compression reading for 81 yz250?

[cleopatrisha]

Does anyone have any idea what the compression on a 1981 yamaha yz250 is supposed to be at. my clymer book does not have any specs for this? I am getting a reading of 150psi on my guage. The bike runs fine but I would like to know when I should do a top end.

 

[2 strokes for life]

I would just rebuild it. How old it is it could use a new top end. In all of my old bike i always rebuild them. I am not sure but 180 is what my IT175 made new and 120 worn out.