750S - which Borrani rims?

[pkrpkr]

Because previous topics are while back I thought I'd start a new topic.

Can anyone help me out with info about the correct Borrani rims for my 1974 750S?
Judging from the frame number the bike was produced in the second half of the production run.

It has a WM3 2.15x18 CROSS 4666 rim at the rear which might be correct.

But the puzzle is what needs to be at the front.
I see WM3 2.15x18 on most pictures, but Ian Falloon's bible specifies WM2/1.85x18 i.e. the same as on a V7 Sport.

Could it be that the early 750S models had WM2 at the front and the later ones WM3?
Also, it seems that the rims can have 4745 or 4746 numbers. Am I correct that it should be 4745?

Thanks in advance for any info,
Peter

[Canuck750]

I cant help you with the detailed answer you are asking but when I found my 750S it had non stock rims (chrome steel) on it and I replaced the front and rear with Borrani flanged aluminum rims.

The 750S parts manual calls for a front as part # 14610801 (V7 Sport 14610805) and rear as 14630700 (same for V7 Sport).

The factory shop manual calls for the rim size for V7 Sport and 750S as Front WM2/1.85 x 18 and Rear WM3/2.15x18 and the 850T as Front and Rear as WM3/2.15 x 18.

I had two V7 Sports - 1973 front drum brake with Record Cross rims front and rear, they had WM2/1.85 front and WM3/2.15 rear.

On my 750S I installed a front rim from a 850T Borrani Record WM3/2.15x18 and a V7 Sport rear Borrani Record WM3/2.15x18

[pkrpkr]

On my 750S I installed a front rim from a 850T Borrani Record WM3/2.15x18 and a V7 Sport rear Borrani Record WM3/2.15x18

Thanks Jim!
I haven't seen a 750S yet with the 1.85 WM2 at the front - not that much around :-)
My theory is that either the 1.85 WM2 has been replaced by owners (the previous owner of my bike didn't mention the type but told me it broke during tyre change so he replaced it by an Akront), or the factory used up the WM2's and during production changed to the 2.15 WM3's.
My 750S is in the second half of the production run and the Germans usually specify "approved" configurations on the vehicle documents. My document specifies: "A.F. Borrani WM 2.15x18, or generic 3.50H18". No mention of WM2.
Think I'll do the same as you with my front wheel rim.

[cliffrod]

Also, it seems that the rims can have 4745 or 4746 numbers. Am I correct that it should be 4745?

Thanks in advance for any info,
Peter

I understand the last four digit number to be a part number specifying the spoke hole drill angle from the borrani factory.  In turn, this dictates the appropriate application for a given hub or motorcycle.  the few undrilled NOS rims I had didn’t have that last four digit number.  It’s not uncommon to have “borrani” “record” “cross” or that last four digit number to be hand stamped. so there may be a catalog of drill angles & part numbers so that when done properly the correct number can be stamped onto the rim for identification.

That four digit number may also be related to the rim profile in cross section, but I’m not sure about that.  The reason I mention it is because the Cross rims on a V7 Sport (and some other Guzzis) have a much more prominent flange or shoulder than the typical Cross rims which are simply thicker than a Record rim.   I’ve had quite a few regular Cross rims and know there are at least two different profiles as mentioned.

This is only an incidental knowledge, learned after owning dozens of Borrani rims in all conditions from NOS to well-used.

[Rolf Halvorsen]

750S

Front: 4745
Rear: 4666

Rolf

[73 sport]

     My V7 Sport parts book and the work shop manual specify WM2 for the front wheel. My twin disc Sport has a WM3 front wheel. Build date December 1973.

[Canuck750]

My 750S was imported from Germany to Canada and ended up in Vancouver, it then changed hands and I bought it as a project off the second Canadian owner. The frame headstock has a metal tag with German nomenclature. The Serial number is VK*___012* (left out the first three digits). The bike had been in a fire at one time, the headers and cross over showed signs of a fire with bubbled chrome. previous owner had repainted frame, non stock rims, controls, calipers, shocks, signal lights, instruments, wire harness etc.....



I have tried to return it back to stock as much as possible. Added a Brown side stand and had the calipers drilled.