Bimmer, Beemer, or Beamer? What Is In A Name?

I know this has been hashed out before, but we still have folks who do not understand the difference, or just don't recognize it.

So, here it is again, from several different sources.

Bimmer vs Beemer
Enthusiasts vs others

Definitions: Bimmer - proper accepted slang for BMW cars. Most people don't know this.Beamer/Beemer - proper accepted slang for BMW motorcycles. You will hear this term used incorrectly by many people. Bummer - When you get a speeding ticket. Bitter - Another German car. Very rare; hand built.
So just why is a BMW car called a 'bimmer' not a 'beemer' or 'beamer'? The answer in part lies in knowing some BMW history and what came first. All real BMW enthusiasts know that BMW got a big start on two wheels, what many call the real BMWs. In those days, BMW motorcycles were quite active in racing, and one of their competitors at the track was often the BSA bikes. Well as things would have it, a track slang developed, and the BMWs were usually referred to as 'beemers' and the BSAs were referred to as 'beesers'. So, of course for any true enthusiast, there is no way that a BMW car could be called a 'beemer', so they were called 'bimmers'. Unfortunately, in the US and Canada, and perhaps other countries, there was a time (kind of still is) where for various reasons, a BMW owner was considered an upwardly mobile person, and of course due to the fun in driving their BMWs most all of them had big grins on their faces. Hence it is little surprise that the non enthusiast types out there incorrectly labeled BMW cars and their owners as 'beamers' or 'beemers'.

© 1998-2007 BMW Car Club of British Columbia http://www.bmwccbc.org/misc/tech-and-trivia/bimmer.html

Bimmer vs. Beamer: The Answer!

So earlier, we lovingly took our Tinseltown-trashin' brother Defamer to task for calling Tobey Maguire's 7-series a "Beemer." We also admitted that we had no reason why BMW's bikes are called "Beemers" while its cars are known as Bimmers. The etymology of the bike thing is pretty easy post WWII, BMW was primarily known as a motorcycle manufacturer, and one of the marque's main opponents on the track was BSA, whose bikes were colloquially known as "Beesers" (or, as we see it in American cycle rags, "Beazers"). "Beemer" was simply a similar nickname attached to the Bavarian bikes to achieve some sort of friendly parity with the machines from Sheffield.

The deviation in spelling for the cars, on the other hand, is a bit murkier. As best we can figure, the car guys didn't wanna be associated with the motorcyclin' hoodlums. So despite the fact that the names sound identical, apparently a vowel swap was enough for the four-wheeled motorists. We still don't get it, but that's the way it is. [Thanks to the Dubba-dubba-dubba-dubba-dubbaya Bee for the tip.]

http://jalopnik.com/139926/bimmer-vs-beamer-the-answer

Bimmer, Beemer or Beamer? What is in a name... A search in Google for the keyword "BMW" yields results that use the terms - Bimmer, Beemer and Beamer. With so many terms being used it is quite easy to get confused. Which is the right one to use? The truth is that all the terms refer to BMW vehicles. However, Bimmer is the proper term for BMW cars (vehicles with 4 wheels) while Beemer and Beamer are terms that are used for BMW vehicles that have less than 4 wheels (e.g. motorcycles). Why all this different terms? BMW started big in motorcycles and was very active in motor sports back then. One of their biggest competitors at the racing track was BSA - which was also a big name in motorcycles then. Since BSA motorcycles were known as Beesers, BMW fans decided to call BMW motorcycles Beemers. As time went by, different people (who couldn't spell very well and didn't take the initiative o find out) started to use the term Beamer. BMW went on to design and manufacture cars which subsequently outshone their two-wheeled cousins. The BMW car enthusiasts wanted a new term to differentiate cars from motorcycles and coined the term Bimmer. The vehicle below is a Beemer/Beamer - notice that there are only 2 wheels?

http://www.bimmercenter.com/article_001_name.html So,.... there.  Now you have it!  :)