The home side started superbly with four converted tries in the opening 20 minutes earning them the bonus point.
A Nino Cutino break saw Mikey Whitton go over for the first try after four minutes and five minutes later Jordan Wakeham stole a line-out and went over for a second try for the hosts.
A lightning break from the home side saw James Perrett score a try, converted for a 21-0 lead on 16 minutes and four minutes later Wakeham's second try secured the bonus-point and a 28-0 lead.
An unconverted Moortown try on 27 minutes, followed by a converted effort six minutes later gave the visitors hope but the Silver Royd side went 35-12 up when Wakeham went down the blindside and fed Jonty Holloway, who scored in the corner.
Moortown scored another try early in the second half, and, although Scarborough did not impress after the interval, they went 40-19 ahead through a Tom Harrison try.
The away side launched a late flurry with an unconverted try on 76 minutes and a last-minute converted try to make the final score 40-31, but Scarborough had done the damage in the first half and claimed another vital victory.
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