Mark,almost none of the junkers are running resrictors. I was doing it from the first winter owning a b1 mainly for hand warmers,after wintering in FL for 3 yrs never needed to worry bout it.but yes the main reason for the ? is to find the right temp. 120 sounds hot to me.
Currently im restricting the water out of the head down to about .250 and diverting the other pisser off the pipe running a long smaller line up the pole with a T to both grips.I need the pressure to get the water up this far with flow,so restricting off inlet wouldnt work for me anyway,puzzling why anyone would do that?
Chuckie..How does a cold motor perform compared to a warmer one. My Turbo cars always run better cold before everything is heat soaked