Mancienne, who looks certain to captain England in their European Under-21 Championship opener against Spain on Sunday, joined the German club 11 days ago, having spent almost 15 years in the system at Stamford Bridge.
"I think the move will have a great benefit," said Mancienne.
"It's a new challenge for me and to play for a big team such as Hamburg and to be playing week in, week out.
"I'm really honoured to go there and really looking forward to the challenge."
Mancienne will become only a handful of English players to have braved a move to one of Europe's top leagues in recent seasons.
He claimed it was a mystery why more of his compatriots had not followed suit.
"To be honest, I don't know," he said.
"I saw it as a massive opportunity to go abroad and to play in the German league, so I'm really excited by it.
"I did have a few other options, but I saw Hamburg as my biggest option."
Source: PA
Source: PA