Jockey Sam Waley-Cohen believes Long Run's class will come to the fore when he tackles the unique Aintree fences in the Grand National.

The amateur rider already has the 2011 Cheltenham Gold Cup on his resume courtesy of Long Run and while the horse has not been as impressive as hoped recently, Waley-Cohen says he can step up on April 5.

Well beaten in two initial starts, he unseated Waley-Cohen in the King George on Boxing Day but bounced back to winning form when dropped in class at Kelso last month.

"We're very happy with him. In many ways the season hasn't gone to plan, but we went to Kelso and that was a great confidence-boosting run," Waley-Cohen told Channel 4.

"You need a horse with class. If a horse can't travel comfortably, you're in trouble."

The Aintree fences have been significantly altered in recent years and while Waley-Cohen admits Long Run may not have tackled the race without the changes to the obstacles.

"They're a bit more forgiving and you can get away with a little bit more," he said.

"We wouldn't have (run him over the old fences), there is truth to that. He's gets a bit casual, he runs into one or gets racing and gets a bit casual.

"When you see him meet a fence right, he really uses himself well, he's neat and powerful. With the National fences, they back them off and they can think about them and respect them."

Long Run is generally at 20-1 for the famous steeplechase which carries prize money of STG1 million ($A1.83 million) for the first time.