Friends - I have a Gipiemme crank with same brand pedals on a project I am putting back together. Early to mid 80s FWIW and both pedals measured 9/16 x 20tpi with my calipers and thread gauge. The pedals don’t thread in easily like most stuff I have worked with. For a test ride I was going to slap on some MKS Sylvans and they would thread in by hand maybe 1/8 of a turn and stop. Here comes the science;

Said Gipiemme pedal easily threaded into an SR crank I had laying around and the MKS did too, naturally.

I cleaned the Gipiemme pedal and crank arm threads and little difference spinning in/out. The MKS was still a no-go. Not cross threading.

My theory - the crank arm threading is kinda marginal from new. Low mile components, I believe. Zero rust on anything, very clean bike.

Do I lean on my pedal wrench with the MKS pedal? I’m reluctant to do that but I believe this era was the twilight years for Gipiemme so maybe the machinery was a bit tired and QC was lax?

Input appreciated!