Danny Elstob, 26, from Wakefield, had been at the emotional ceremony for his uncle on Monday afternoon when unscrupulous thieves managed to get away with his black Honda CBF125 from the car park.
He was devastated to find it had gone when he came out of the Wakefield Road building.
His girlfriend, Lauren Tansey, 22, told the Express: “It had been parked in between two cars and hidden from the road but it had gone.
“He went looking round the car park but it was nowhere to be seen - he’d only just got it.
“It was a present from his dad. He was really upset, it was a bad enough day with the funeral of his uncle - it’s been a bad few weeks and this was just the icing on the cake.
“He usually puts three types of locks on it but he only put the standard lock on because he never thought anyone would steal it at a funeral.
“We aren’t sure how they removed it, they may have just lifted it into a van because it wasn’t a heavy bike.
“There’s been a couple of people who think they may have seen a black bike here or there but there’s a lot them about.”
CCTV from the crematorium is now being checked to find those responsible.
Meanwhile, anyone with details is being asked to contact police on 101 quoting the crime reference number 13180476688 from Monday, September 24.
The bike’s registration number is NG13 KHV and it had been taken sometime between 1pm and 2pm.