Hello @Pierre-Etienne ,
Nice to hear of You here.
As I read, the tri-lock system is out of stock, i’m about to come with an extremely cheap and practical solution in maybe a week from now.
A 12x2 mm aluminum tube has already arrived and I am about to collect my 2nd Strida, an LT, on Tuesday.
Busy until Wednesday. That‘s why I’ll need to find some time.
I will give an additional discussion of the Achilles-heel topic regardless of the comprehensive discussion given by @Blackstridaaustria already - hopefully, I’ll be able to add further insights.
A first thought: i consider it unlikely, that You will need a new tube. Most likely, You‘ll be able to repair eventual damage of the bottom tube.
regards: Klaus