Dl 650 V current, does not start, loud metallic hitting

Good morning love community I drive a V Strom Dl650, built in 2007 with about 55tkm. It stood 1.5 years relatively much, I drove when it came up only 2,000km in time. I had it standing in the garden on the house wall and covered. Anyway I wanted to start it and it sounds like the starter is very sluggish and has trouble turning. If it is then over the “dead point” there is a loud metallic blow, instead of that the engine starts. 2 weeks ago had I did that too, but then she jumped on. I drove half a day and so far everything went. Now I wanted to throw them up and take them to the workshop. However, this is so loud that I hardly dare to try again. Such a crap. Does anyone have an idea what’s going on? Best regards, Heribert40k