I was working at Spinetti´s Bike Shop when I bought a new 1978 SP 370. It was a nice little machine, well-mannered and reliable, but had no power, no suspension to speak of, and was too heavy. I rode the %!¤ out of it. Every time something got broken or worn out I would make it better. The steel tank and fenders went early--replaced by plastic--and the handlebars. After completely wearing it out I installed a 410cc piston, 36mm Mikuni, White Bros. pipe with Super Trap muffler. Shortly thereafter I broke 2nd gear powering out of a sandy turn; replaced the entire transmission with the ´79 version, supposedly updated. Ran it hard for another two years, worked fine. I lost many pounds throwing away the stock pipe. Lost more tossing the stock airbox/battery box--and the battery too. Using the leads at each end of the generator coil (abandoning the center tap) I found plenty of power for a 12V, 60W headlight I cobbled on from a CB750. Putting the output through a full-wave rectifier and putting two 6.5V zener diodes, in series therefore gating at 13V, in parallel with the load, which was now only the headlight and brake/tail light. For two years I had a commute on about 15 miles of dirt road, often in the dark; lights worked like a champ.
Finally there was nothing stock about it but the actual frame and the engine cases. Warmer cam, White Bros. aluminum swingarm, a fork kit in the front--giving a quite functional 9