So, I read that the oil seals for the front forks were the same for the subject bikes, but when I bought the BMW seals they are thicker than the original (?) Ducati seals. They are enough thicker that I can't get the lock ring in above the seal to hold it in place. Did I get the wrong BMW seals, or is there another trick to get these to work?

I'm no expert, but it's apparent those won't work. Are you sure you shouldn't have seals for a K100 BMW? I think that's a different animal altogether.

I got my info from this post
viewtopic.php?f=3&t=3889

Maybe not all parts are the same.

My seals are much closer in size, I just can not get them seated.

My typical solution is to use the old seal, a large socket, and a hammer.

But, the stock seals from Marzocchi are still available at the Ducati dealers for €. 17...
So, I'd buy those ones .
Ciao

I just bought seals from the BMW dealer, $17.33 each, they had them in stock, exactly the same. They fit the k100 RS.

The last time I replaced my seals I used the OEM 907 seals and they started leaking about month later. I took them out and replaced them with 900ss seals I just happen to have. Same outside diameter and same inside diameter. They where however a little taller. So I sanded off the rubber coating on the bottom and left out the washer on the top so I could get the retaining ring on. They have been in for about 4 years now and no leaks. The 900ss seals are more robust than the regular 907 seals.
du907

that looks like a k100 seal, not a k1100 seal. the k1100 seal is the exact same as the 907 seal.

pn-31422312928

viewtopic.php?f=3&t=2395&start=0

The BMW part numbers that I quoted in my post are EXACT replacements for the 907ie. They are made by Marzocchi and have the same Marzocchi part number molded into the rubber. You have the wrong seal from BMW. Check the part numbers in the post again.

Sure enough. Went to the BMW dealer (vs buying the pyramid replacement part online which was the wrong seal) and they had the correct seal in stock. Thanks for the help.