I've just bought a Kilimanjaro bicycle for cheap. One reason it was cheap, I expect, was the gears system. It's only partly functional, and I don't understand why. I would go to the bike shop with it, but they'd charge me five times as much as I've paid for this bike, and I still wouldn't have an idea what to do if this happens again.
Rear gear minimum position (second-to-smallest ring):
I somehow forgot to take a picture of the maximum position, but it's like two rings up. I'd like it to be able to go to all rings.
Front gear:
It only goes to the lowest and middle ring. I'd like it to go to the highest one too.
Front gear control:
Rear gear control:
Is there anything I can do to fix it?
EDIT:
I've made a video showing the shifters. Does this help identify what's wrong? Do I really need to replace them?