slow down ....... any older Boardwalk has a 1 inch or maybe a 1 1/8 steerer tube with the threads on the outside of the fork....
Radius 5 has the threads on the inside for the cap nut to hold the handlepost in place..or lets say to adjust the tension , just like an ahead set system stem on a "regular" bike ....
Yoy cannot swap the old system to the newer stem ....
thor
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