I got a bunch of Indian parts and amoungst it was 4 bolts NOS but dont know what its for . maybe post 1953 "Indian" , royal enfield etc
the thread is 3/8-24 , the end stub is 1/4 dia x 9/16 long . the hex is 5/8 .

whats this type of bolt called ?
Its some kind of locator . I doubt its for rear stand on that 1/4 stub . I know theres a long bolt similar for the battery frog on 741s its like 3" long .
anyone seen one of these before ?
possibly car transmission or something off HD servicar or Indian dispatch tow
Indian gear shifter uses a ball and spring for the gear locator . I had a look at the vertical scout site 1949-52 , doesnt look like it belongs there either .

Sporty ?
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Looks a little like the plastic throttle lock / idle screw that they use to have under the accelerator

its looking like its a motor drain plug HD #700 , 3/8-24 , 1911 to 1970

but I cant find a pic of a magnetic one with a stub 9/16 long . could still be for a car motor or trans

Indian trans case has 3/8-24 drain but its taper thread . indians usually have grits from the crash box gears