Thanks, guys, for all the measurements, input, and illustrations; they are surely helpful!
I found a nice illustration of the AXA on a v-brake mount here:
http://www.dutchbikebits.com/index.php?route=product/product&product_id=220Still, I still don't think I can fit a ring-lock to Sherpa at the usual location! I'd have to give up my HPX pump to mount it in front of the stays, and there doesn't appear to be enough clearance beneath the rear rack stays to clear the lock if I mount it to the v-brakes (a location that is outside the frame and therefore vulnerable).
After reading your notes, I pondered placing it atop the chainstays, but I think I might be about 3mm shy of the lock body clearing the bottom of the front derailleur when it is on the small chainring. It looks like I would have enough chain clearance, and it appears a ring-lock there would also clear the chainrings and left crankarm. It would keep the weight low on the frame and still be secure inside the rear triangle. I'm guessing I'd need the NKR version like you got, Pete; the key might just clear the chainrings when un/locking. Would water intrusion be a problem with the lock horizontal in this location if I use fenders? Maybe an Amparo like yours would differ just enough to make it possible.
Jim...I sure appreciate those photo-measurements on the AXA Defender. That 50mm opening is narrower than my fenders, but I could work the lock around them for installation. If I could get the tire profile to fit mostly in the 63mm part of the slot, then I might be okay (my 2.0 Duremes are 47mm wide at medium pressure on my Andras). I could always remove/insert the rear wheel with the tire deflated and then pump it up
in situ. I'll have to measure this tomorrow morning when I can better see the clearances involved.
Best,
Dan.