Yep, that skinny nut that holds the front drive sprocket. How to lock the sprocket against 200ftlbs:



A picture tells all. The longer story...

Found '95jy's' post from a few years ago (https://www.hdforums.com/forum/prima...l#&gid=1&pid=1), which is a bit of belt attached to a wooden wedge.

Nice idea, I can make that, I work on 50cc&125cc twist-and-go scooters, I've got loads of old variomatic drive belts lying around, and lumps of wood.

So I found a belt. And I looked at the sprocket. And I thought, there's a handy looking big stud.

2 minutes later, I was swinging on the end of the breaker bar like a chimp.

Hope this helps someone else. Your local twist-and-go 'ped repairer will have a bucketful of old belts, they get swapped out at 8-10,000 miles.

--
Mike