TOPIC:

H All, I had to buy this set up! Of course this hub needed some saving. No welding, just 4 Heli-coils. I upsized to 3/8" bolts.  And I turned .015" of ugly off the sprocket adaptor.
Common Z1 / KZ Double Weld Drag Bike Rim back before they made wide rims.
Hubs are universal, same both sides. This one has 2 - 3/16" flanges.
My questions are? Can the 4 bolt disc just use the 4 bolts instead of 8?
Plus this one must have used the sprocket extra spacers, which in turn, took sprocket off of flange. Then proceeded to elongate the holes.
So until I polish this whole rim ring! Winter project. I can not tell until it's laced. To see if I need a spacer at sprocket? Most likely had the bigger drag slick on it?
And try and find an old school spoke trueing person! I can get it together, but do not have time or patience to true it up!
But this will be a street tire project. 180? 200? Or a Grooved cheater Slick! 
I know a couple of you old timer drag bike guys might have some info!
Thanks in advance!

Marty in Buffalo

Hey Marty
My 2cts is 
8 bolts is what I would do 
Where holes were oblonged  . Did the bolt have a shoulder , or was it threaded where it had bearing against the  disc or sprocket ?
Can you  check sprocket clearance by finding the overall tire width of the chosen tire vs the  disc / sprocket assembly and pull some figures from that to see if you are at least close
I mentioned in another thread I found in my secret stash a 1980 Kosman  catalog with price sheet if I can look up anything in the future you may need
And I can e mail you the pages you may want 
Dave

I have a NRC catalog from 1988 that calls out the Kosman wide rim at 5-3/4" x 18" that will fit a 8-1/2" wide slick. Listed cost back then was $500.