I got a call from Ralph Weidling at Bultaco Parts US. The salvage Model 143 Frontera motor I sent him has been completely rebuilt, and has great compression. It’s mostly a stock Frontera 360 (circa ’75–’76), but the missing head has been replaced with one from an Alpina 350; it was available, affordable, and it drops the compression just slightly for more reliable street use. It has a new Vape ignition with high-output alternator. A Mikuni 38mm VM roundslide will be arriving along with it. I’ll should have it in my hot little hands within a couple weeks. Ralph texted me these photos.