[JBH316]

I think that if he is still able to do everything that he normally does without too much difficulty and is still happy, then it's probably not time to make that decision.

I had my 2 year old hybrid put to sleep last weekend. She had mammary tumours diagnosed on xmas eve and the one in her groin grew very rapidly and started to affect her back leg. She was no longer able to climb her cage, use her flying saucer or climb over things - all things that she LOVED to do. She was still eating but less than normal and had started losing weight. She was still bright enough but I didn't want to let her get to the point where she was really struggling. Had she been a lazy hamster, I probably would have been able to let her go on for a few more days but it was the right time for her.

That is how I judged things for her but I do think you will instinctively know when it's time so I wouldn't fret too much about that.