Modern Vespa

First of all I must say MV looks like very nice forum, I've been lurkin around for some time but today I bought meself my first Vespa, a PK 50 XL. I've had few motorcycles before but for some funny reason I've had the Vespa fever for some time
I hope somebody can help me with a minor issue I have with the PK. I can not attach its original sidemirror because the "hollow bolt" just moves around with the 17mm fixing nut which can be (barely) seen on the pic attached. I wonder am I missing some parts or how should I tighten the hollow bolt?

Mine doesn't quite look like that I think. The mirror threads into the bottom portion of the headset. Mines stripped. If it is it will just spin round and round. Not too sure what your describing or looking at. Are all the threads good?

Yes, looks like the threads are ok. The system i have has 4 parts (from bottom to top):
1. Hollow tube with outside threading, it is in the headset
2. rubber gasket (just cosmetic/weather protection)
3. 17mm nut
4. the mirror itself, it does not have any threading, it is fixed by friction as the 17mm nut tightens the hollow tube
The problem is that part #1 (hollow tube) is loose, not entirely but it rotates with part #3 when i try to tighten it. I do not get it how to fix firmly part#1 as it just turns freely in both directions...

The threads that holds your hollow tube to the bottom of the headset are stripped.
Fix 1: Epoxy the hollow tube to the headset
Fix 2: Get mirror bracket that mounts to the underside of the headset
Fix 3: Clamp on legshield mirror


just my opinion, yours may vary.

Yes, thanks for the advice, I think I'll get a new clamp-on accessory mirror, the old one is pretty worn out and ugly anyway!