This Carb is a replacement carb on some Pursang, Frontera and Astro models. Adapters are needed
for some models. They come pre jetted for each model. Some models may need fine tuning. The engine side of the carb dimension is 43mm and the air box side of the carb dimension is 62mm.
Mikuni Carburetor 38mm
Please supply your Bultaco motor serial number so we can jet the carb for your application.