Zweite Hand Zweirad

This review is coming from a visitor to Berlin with multiple experiences renting, owning and repairing bikes.
Zweite is a perfectly good place top rent a bike, with fast service and reasonable prices (€ 10/​day). The bikes are step-​through cruisers with baskets, front and back lights, a bell, and three gears — all features standard to many bike-​share programs. They also come with a lock and a seat adjustment before you get in the saddle.
The bikes themselves, though, are not ergonomic. I’ve ridden faster, more efficient bikes with the same upright cruiser design. Also, the gears on my bike needed serious work. They took a strong wrenching on to get them to shift down, and even then, the dérailleur clearly needed serious alignment. But to be clear, the bike was still perfectly safe and functional, but more or less as a single speed. Store hours are also inconvenient: 1200 –1800 on a weekday. That makes it impossible to get an early start unless you pick up a bike the night before.
Overall, this is a perfectly adequate place to rent a bike, with only a few minor downsides. Use their service, but be sure to plan ahead.

We have a very bad experience there.
We hired two bikes here.
They did not have al the sizes, but that did not bother us.
After an hour or so the first bike had a flat tyre. That, s a problem when you are on the other side of Berlin. So we took the bike for a repair at a bike shop downtown. It turned out that we drove on a dangerous bike. The state of maintenance was very bad. We put on a new tyre.
Next day another tyre went flat.
On returning the bike the guy at the shop saw the flat tyre and started shouting. Did not listen to our story, was very aggressive.
We did not get some money for the new tyre and in angry the man told us to leave.
Do not rent a bike there!