In the UK Bultacos are referred to by year. Compared to say the States or Canada this is how they registered their bikes in that country. When a bike was brought to the UK it was documented on which day and which year it was brought in; I'm guessing this was done at comerfords but could be wrong. Effectively the "country" designated the year of the bike. While its accurate that bondy's bike is an 81 model according to when it was imported, this is a very inaccurate way to identify a bultaco. To say a 199A is a 1979 model year is misleading. They built the 199A in 79 and 80 possibly even 81. When ordering parts for a bultaco you can't just say " I need a piston for my 1975 350 sherpa t"........ Ok which sherpa t would that be ?. The Model 151 or possibly the 159. Both were made in 1975. Model numbers are the most accurate and only way to correctly identify which bike it is. While it may be of some importance or value when registering a bike it is of no consequence when proper identification is required. My M199B had the serial 13456. I know factually that the 199B serial numbers went right up past 14200 or so. To try and determine the year it was built would be difficult. Unless someone from the uk has a serial number in the same range as mine was and can tell me when theirs was registered . And Bondy.... if you have a 198B that is a very rare bike.
Steve