Vintage BMW Motorcycle Owners

Two bike of Willy Neutkens Collection:
BMW R63 number 4
BMW R42 NO number

Now the question is:
All the R62 and R63 have the numbers 3 or 4?
and
What is the meaning?

Ciao Luigi

...other pictures, R42 no number, R62 number 4.
The search continues.
Luigi

Many tanks Kurt, I still learned something new
, at least now I understand more about the numbers stamped on the crankcase of the motorcycle of 50s years.

Hello Friends I've one questions about one big number on the carter of the R63 motor. In the left side, in upper-left part of the motor, near the magneto Bosch, there is one big number in carter fusion (sorry for my english). Please see the two pictures: in the first there is Number 3; it's about on...

Hello Bruce
Yes I live 200 km from museum that you have send me.
But the spotlight/mirror of the zundapp is similar but non like that I've find.
CIAO Luigi

tanks schrader
but the kind that you said is for post war model
this is not Hella and I can't understand how put on the handelbar..
Ciao Luigi

I bought this as a light mirror to put on the handlebars of my BMW R52.
Someone has already seen?
It has no made, no signature.
I think it was for a car
You have idea how the light were attached on the handlebars?
Grazie e Ciao a tutti Luigi

Thank you for sharing your insight Ian.
Luigi

No Darry, there isn't a reason.. it's mistacke , the BMW arrived in Italy in crate in this condition. I've see the email from the seller and him tell me about the story of the bike: """Hi Luigi, Was just thinking last night that it's taking a bit long for the bike to arrive. I went to...

Yes friends, the bike is like R6 model...and I've write because I had find it in South Africa too.. but, the story is: I put one message on a Russian site, that I was looking for a R5 frame.. Sir. Guy Gordon Jenkin wrote me from KNYSNA (near George), and send me pictures..WOW! This man transport the...