Serial/frame identification numbers, year, code, power output, from the earliest BMW motorcycles to mid-1990's (Snowbum)
This article, with different editing, and possibly some differing details, can be found at:
It is article 67C on that website
© Copyright 2020, R. Fleischer
NOTE! Careful as I think I usually am, there may be errors in this article, from typos, transpositions, to outright wrong information gleaned from various sources, yes, even factory information. Please report to me if you find any errors, typos, etc. I'd appreciate knowing specifically the error/problem, so I can look into the details. Thanks!
(1) This article's information was gathered from quite a number of sources, places and publications; but especially from several old factory (German literature) publications. It is believed mostly, but not absolutely correct. BMW factory literature varies in production numbers and serial numbers for quite a few models. BMW has, at times, confused...and mixed-up...their own figures. This has been particularly so when BMW has used both reserved serial numbers range for a model; and, serial numbers for actual production. BMW vehicle numbers are the serialized number of the frame or engine or both, the more modern versions of which can be 6 or 7 digits, and can be seen on the engine, and/or frame. After ~1980, the numbers are usually the last 7 digits in the new 17 character VIN numbering system, but this is not universal for all Country's shipped-to. From 1984, BMW stopped stamping serial numbers into the area next to the engine oil dipstick. There is a LOT more to all this. See (5) below; and, see my companion article: https://bmwmotorcycletech.info/IDnumbrs.htm.
(2) For much more information on 1923 to modern BMW motorcycles, including photos and detailed specifications, one of the best references is the Illustrated BMW Motorcycle Buyer's Guide, written by Stefan Knittel and Roland Slabon.
(3) This article is arranged alphabetically and then numerically, so it begins with K bikes. Where total production is shown on only one line, it usually applies to total of all production serial numbers for that model and coverage years, as best I know. There is no specific reason, except for readability, that I used separate tables instead of one table.
(4) Kw (kilowatts) was measured by the at-that-time/year-version of the German DIN method. BMW may sometimes measure in Hp, and not via mathematical conversion...but that, and the details of the method, and hence accuracy relatable to today's Hp is NOT known for sure by me. In modern terms, 1.00 Kw = 1.34 Hp. That mathematical conversion was/is not absolute in the real world, particularly back in the Sixties & Seventies, as many Countries used differing engine measurements methods. An example is how American manufacturer's determined power output up until the eighties...I refer you here to what is called Gross horsepower, Net horsepower, and SAE power. Take your pick. While engine conditions of atmospheric pressure & temperature of the incoming air for combustion had an effect, 'power robbing things' like exhaust systems, water pumps, intake tract temperature, etc., usually had a considerable effect. For some engine or vehicle manufacturer's, everything possible was done to eliminate such power losses during measurements (so as to boost the results), so the actual engine output of the car or motorcycle was always less, sometimes substantially. In general, to compare to old style American Hp measurements, I suggest you subtract a MINIMUM of 15% from SAE/American figures, to get reasonably close to DIN (well, modern Hp) figures. BMW often dually-published both Kw and Hp figures....and in THOSE instances, the Hp figures are calculated, not measured, from their correct Kw figures. In other words, BMW used the 1.34 factor. DO NOT USE Hp & Kw directly nor absolutely for any type of comparisons with other manufacturer's of motor vehicles. Where power is shown in parenthesis in this article (xx), that is Hp, due to conversion. Sometimes two or even three values for power output were used, depending on country, etc, but the bikes are usually identical. NOTE that there is plenty of confusion about the power output of the quite early motorcycles, with some publications mixing up Kw and Hp. I will straighten these out on an ongoing basis, when/as I have the proper information. AGAIN... NOTE the column headings...if enclosed parenthetically (xx), that means Hp, calculated.
(5) Code numbers (and sometimes serial numbers) are quite useful at times, in helping to determine such as wiring and equipment specifics; and, in some instances, the variances for the engine power output, etc. BMW produced SOME models in both low and high horsepower ratings for situations wherein Kw (Hp) determined insurance and/or licensing categories in some Countries. In most instances, where the code number changes on a specific model during production, I have separate lines for them. When a model number is listed, followed by one or more categories, the first entry, top line, will usually indicate the total production for all years for that model. Unfortunately, information on ALL countries' production was not always available, although USA shipments were more accurate. Year/Production may not be entirely accurate, see my articles 67A and 67B for an in-depth look at ID numbering, etc. I've used the best information I can find for production numbers. Note that production quantity will usually be at variance with "reserved" serial numbers. Where information is in conflict on serial/frame numbers, I generally used BMW's own publications. Where serial/frame ends in 0000, that USUALLY means a BMW reserved number and not a specific production number. Where the serial/frame ends in a very specific number, that means the true end of that production run....but, sometimes I have to add parenthetical numbers, where information differs.
(6) CC may be listed as category (600 for example), as done by BMW and others, or, true (594 for this example). I generally use the advertised number, rather than the specification number.
(7) I have generally followed BMW's own literature on the G/S and GS, although BMW has not been consistent, nor have others. One problem is misuse of G/S and GS. The first model was the R80G/S; and, in general, from ~1988, the R65, R80, R100 versions are GS. If you see, as an example, an R80 G/S heading for, say, a 1988 motorcycle, it is really a R80GS.
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