Joined: Jan 2010
Posts: 9,808
Likes: 1,781
From: Northern California
Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
Campagnolo and Trek Matrix come to mind as far as being narrow.
Even Ksyrium SSC and Elite wheels were only 13mm inside width for most of their production years, as was the wide-looking MA2/MA40 rim!
Nisi Mixer rim was the narrowest inside width I've seen, possibly less than 12mm!
I just bought a pair of older Bontrager Race Lite wheels that had a refreshingly-wide 15mm inside width.
Are you looking for narrower rims? Should be able to get those cheap.