The title holders scored thrice in the opening half and with the bonus point added in a blitz shortly after the break, Saints kept their foot to the floor for a resounding result.
“The first game is always tricky when you've not played much rugby as a group,” Hopley told SaintsTV. “But there are plenty of positives for us to take forward from today.
"Obviously it gives me great personal satisfaction to see the forwards scoring from some driving linnets but it was also good to see the Segun brothers on either wing finishing off some good moves.
"We're under no illusions though. It's only our first game of the season and there is plenty still to work on. I've no doubt that this group will continue work hard though moving forward."
It took just three minutes for the scoring to start, Harry Mallinder smashing up the middle and Lewis Ludlam crashing over for the first of his brace on the afternoon.
After seen the backs provide for the forwards to score, the pack would repay the favour. Having dominated the scrum in the opening exchanges, they turned screw with a lineout drive and Rotimi Segun muscled over beside the posts.
That second came following a flowing response from Yorkshire through Dan Tai, but was to be the only glimpse of magic from the visitors and Saints crossed again before half-time.
Again it was Segun and again it was the forwards who laid on the score, picking and driving into the Carnegie 22 before Mallinder floated the scoring pass out wide.
The skipper, who also added five of the seven conversions from the tee, was over himself soon after the break to provide the bonus score and within moments of the restart Tosin Segun added number five.
Ludlam doubled up with a neat step and go beside the posts and on the hour, Rotimi Segun bagged his hat-trick to round off an impressive afternoon for the reigning champions.
The Saints Under-18s face a tough trip to Tigers next up in the Academies League on December 20th, a curtain-raiser to the senior East Midlands derby that weekend, but not before a friendly at Saracens seven days earlier on the 13th.
3mins SAINTS Try Ludlam Con Mallidner 7-0
11mins YORKS Try Tai 7-5
21mins SAINTS Try R Segun Con Mallinder 14-5
31mins SAINTS Try R Segun 19-5
HALF-TIME SAINTS 19 YORKS 5
40mins SAINTS Try T Segun Con Mallinder 33-5
52mins SAINTS Try Ludlam 38-5
60mins SAINTS Try R Segun Con Mallinder 45-5
FULL-TIME SAINTS 45 YORKS 5
SAINTS U18 Shaw; R Segun, Hutchinson, Mallinder (capt), T Segun; Grayson, Smith; Palmer, Davison, Jeannot, Moon, Hawkins, Cardall, Ludlam, Cox
Reps - Marmion, Cave, Byrne, Trinder, Allman, Morris, Hamilton, McKibbin
YORKS U18 Allan; Gorman, Dunne, Wright, Tai; Smith, McDaniel; Capps, Poole, Dennies, Cherrington, Ward, Longton, Wilson, Sanderson
Reps - Chadwick, Boyce, Newborn, Ma’asi, Hatchwell, Field