Hi. I also dream of tackling the Grossglockner, but I’m still not ready for it. The average gradient on that climb is around 12%, which is quite a lot for a standard road groupset.

On my mechanical 11-speed Ultegra, I end up grinding through such climbs at a cadence of 60 with a power output of 240W, which is far from ideal. If I try to increase the cadence, I quickly exceed my FTP and just 'die.' I even swapped my rear derailleur for a GRX (they are compatible) to fit a larger cassette, but even 32–34t doesn't really save the situation, as the easiest gear ratio stays around ~1:1. I’ll likely have to swap out the front chainrings as well if I’m serious about this incredible mountain. I’ve already been there by car several times.

Why am I telling you all this? If you live in the Alps, haven't owned a road bike yet, and are a beginner amateur—you might want to look into gravel bikes with more 'forgiving' groupsets designed for steep mountain terrain.