Borrani aluminium motorcycle rims and their number system

Borrani aluminium motorcycle rims and their number system

Well here’s something I didn’t think about until today. On some Borrani motorcycle rims, there is a number (other than the usual WM and wheel diameter). It may look like this “RM-01-4701” or “RM-01-4777”.

It turns out that the Borrani rims that have a number like this, are supplied by Borrani direct to a motorcycle manufacturer and were for specific model(s).

Borrani rims that don’t have this number, are ones supplied by Borrani un-drilled, so they can be drilled at the correct angle / offset for whatever bike you want to mount it to.

Decoding the text stamped by Borrani on their Record rims.

Here’s an example: WM3 – 18 40 RM-01-4701

WM3 = 2.15″width of rim

18 = 18″ rim

40 = number of spokes

RM-01 = Not sure but an educated guess suggests that it’s the Italian acronym for Record Model which is the model design of the rim.

4701 = The number that relates to the specific model / manufacturer that the rim is for. Borrani supplied (and still supply) many manufacturers.

They used codes like 4450, 4403, 4607, 4777, 4446, 4845, 4544…

Here’s what I have managed to gather so far:

  • 4544 = Moto Guzzi Le Mans S3 Rear
  • 4845 = Moto Guzzi Le Mans S3 Front
  • 4777 = Ducati 750/900 Super Sport
  • 4446 = Laverda, but I don’t know which model.
  • 4701 = Don’t know. But I have one.

I believe BSA and Triumph also used Borrani’s when the equivalent Dunlop flanged rims were unavailable. However, that might be complete rubbish. I was just told that.

If you can help to build the picture of the Record rim numbers, I will make a page in the “Technical” section of the site so that everyone has access.