Our hamster is huge. He's really big. We just had to get him a bigger cage because he could reach the roof of his old one without even stretching, and that was just a standard hamster cage. The new cage is one of those three tier things with the tubes to climb up and down. Problem is, he's a bit of an idiot and won't use the tubes to climb up and down. I think it's because he's a little big for them, although I've seen him use them occasionally so he does fit through them. Instead, he chooses to fling himself off the top floor of the cage. I'm really concerned he'll break a leg or something doing this.
Considering suing the pet shop for false advertisement - he has to be part guinea pig or something
Guinea pigs don't leap although they are daft enough to try . Can you stick food etc in his tubes to encourage him? Other than that attach a bungee . Sorry not a hamster expert but I'm sure someone more helpful will be along.
Haha our giant hamster is in a rat cage which is basically a massive hamster one. He loves the giant rat wheel more than the hamster one aka the treadmill! Because of the cage height I added large climbing frames and a swing bridge at the highest points so he climbs on these to stop falling long ways. He was never overly gymnastic tho..... I had one that would monkey bar across cages!