Thats a stock type 750 front end with I'd guess 6 .. maybe 8" tubes in it . The way to tell the length for sure is pull off one of the top fork caps.. inside there will be a tube type spacer .. The length of that tube .. is the length of extension..Or .. a stock early (69-76) tube assembly measures 29" from the top edge of the tube itself... down to the center of the axle..

The original Invaders were made by a company called Bill Industries. There were others that made very similar wheels as well ... For instance .. Drag Specialties offered a line of them called Drag Vaders .. and there were others .. Some had different numbers of spokes .. some had offset spokes ..

A Honda neck neck is 7.5 inches long and uses a 48.5mm bearing race on top and a 50mm bearing race on the bottom.. An HD neck that doesn't use bearing cups is 7" long and uses 1.92" bearing races .. both top and bottom .. An HD neck that is setup to use the chrome cups is 5.5" long and has a bore of 1.25" to accept the bearing cups.

The neck on your bike is a Honda type..

Build it the way you want it ..... then learn how to ride it like you own it..
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