"I am pretty gutted because I have only had it about a month," Jacob said. "[Mountain biking] is pretty much my main sport.
"I go after school, on the weekends, in my spare time," he said.
Jacob's mum Mary said her son had worked all year to buy the bike.
Jacob had saved up for a previous bike and had that for a couple of years before buying his new one off a professional mountain biker.
"So it is a really nice bike," she said.
"He got part-time jobs and has done all sorts of things to buy it."
Things such as trapping possums privately with traps he had bought himself, part-time over summer for the Department of Conservation.
"And because we do a lot of tramping, when we go tramping we drop him off in the bush and then he sets the traplines out.
"Starting this time last year, he made about $900."
But all of that seems to be for nought - as a trip to see a sick relative has ended with a year's hard work being stolen.
"I said to my husband to take the boys for a ride now because dad was coming home," she said.
"And then five minutes later he rang to say the bike has been stolen."
Mrs Hulme-Moir said they spoke to hospital security staff but they had no luck.
"Apparently, they have some security but the cameras don't reach to the bit of the parking lot that we were in, so there is no record," she said.
"We reported it to the police and we have been driving around, just trying to spot it, but really it is a needle in a haystack.
"So if anyone sees of hears of anything, can they please contact the Hastings Police Station."