Borbets and Hub Rings - long Q but simple answer

[Indiana_Red at hotmail.com (Ken B)]

Wouldn't reputable after market manufacturers have default "bore" sizes.
In other words, Borbets are usually 60mm and ATS are usually 66 etc etc.
Here is my problem:   I have 4 new (used) Borbet C wheels and am having
trouble getting a good caliper measurement:  63.1mm, 64.3mm, how can I buy
the correct hubcentric rings.  to make matters easier, or in my case harder,
there are only a few sizes out there.
http://www.pure-motorsport.com/products/description.php/II=447   Here is a
simple drop down of what this compnay sells for vw hubs (57.1mm)
More details on my situation:
There is not enough room inside a 15' wheel fo me to extend my only set of
calipers so i clipped a length of 10ga wire and varied the curve of it to in
effect make it shorter/longer and measured the length each time I checked
the bore of the wheel.
Accuracy is not that great but I'm sure its better than a mm either way.
The inner part (closest to the brake rotor when installed) of the bore on my
wheels is a slight lip that has an inner dia of 63.1mm, then flares wider to
64.3mm and the rest of the way in (about 2" worth towards the outer/lug bolt
side) it seems to very slightly taper to about 64mm.
Hub rings with an outer diameter of over 63 seems wont fit over the first
part of the wheel to go on (that little lip) and there appears to be only
one common size under 64 (60mm) according to the above link and another
online vendor I checked.
But a 60mm outside diameter would not be large enough to provide a snug,
positive location on the hub.
have never seen these things instaled and not sure what the trouble is here.
Any advice or experiance would be helpful.
Thanks
Ken
'79 Scirocco 16V "McFly"
"81 Diesel P/U