Engine stampings?
 

Are engine and frame stampings suppose to match? Today I discovered an engine number while sorting out my center stand. It reads as follows...

913063

247/MC3

What are these for? What do they mean? Thanks.

The first number you show is only six digits. If it was a serial number it would have seven. The number 247 is what the basic engine design for all Airheads. BTW R65s are not 247 engines. You might tell us where these numbers are and also what kind of bike, year and model, you have.

I would guess that your bike is a 91, the engine was the 63rd one made in week 30 of 1991.

Hmm, a 91? It's suppose to be a 79 R100 RS. The frame serial is correct for that year and has (7) digits. The engine stamping is located on the left case just above the oil pan.

The 913,063 R100RS made? wouldnt surprise me.

I did find this though:
http://bmbikes.co.uk/chassispages/enginechassis1000.htm

If the motor is from a 79 it would have a seven digit number behind the dipstick hole. This is turning into an interesting motorcycle. Not as in, "May you live in interesting times", I hope.

There is indeed a seven digit number behind the dipstick that matches the frame number.
Here is a pic of the engine case stamp.

http://www.proflorists.net/AAA/enginestamp.jpg

BMW just made their millionth motorcylce just a few years back. Of course, that includes all their models ever. I mention it because I don't think a lot of people understand just how low our production numbers are. BMW also just recently cracked the 1% of bikes over 750cc's sold in the US barrier for the first time ever. One percent. Woohoo! And we are their second biggest market!

Is there a BMW logo next to the engine number by the dipstick?

Affirmative. There is one to the right of the serial #.

The dipstick no. is the frame no. as originally installled. The no. on the pan perimeter flange is the engine no. No mysteries here.

FWIW, I believe the 247/MC3 identifies the engines EPA approval.