Headset keeps working loose - help appreciated.

[Perec]

Hi guys

Perec Junior's stunt scoter has a bicycle type headset as per picture below. It was self-tightening for some reason, and any amount of adjusting seemed to make no difference. It would be okay for a few hours and then tighten itself up again. So I took it to a bike shop over the weekend and they adjusted it using a proper headset spanner.

Today, the headset was too loose and the locknut was loose.

Any ideas why this thing defies all attempts to adjust it correctly and why the nut loosens itself please? Is there a solution?


Many thanks.

[SkinnyBoy]

Years ago we used to use BMX style headset locks and if we had no money we used to drill a hole through the top lock nut and thread a grub screw into it. Thankfully since the advent of thread less headsets I'd forgotten about them hehe