Crunchybeard
Active Member
I have a cb450 1972 honda and the compression on both cylinders are 110 psi. Im wondering what I can do to increase compression. The timing on everything is good, but do i have to get it bored out? I tried lapping the valves by myself, but when i test the leakage with brake fluid, a drop always comes out of the sides of the valve head. Im thinking about taking it to a machinist to clean it and bore it. its popping when i try to start it, but it never happens. any advice would be appreciated.