YMCA moved up to fourth place in Yorkshire I after their most accomplished and disciplined display of the season.
Winger Dave Holmes finished with a personal tally of 21 points, hooker David Guegue was involved in everything, while 19-year-old 6ft 5in second rower Damian Pearson gave a man-of-the-match performance in a dominant pack.
The only thing marring the win was the 80th-minute red card for Ross Housley, who was dismissed for stepping in to assist teammate Neil Walker, who was being subjected to some rough treatment while on the ground.
YM opened briskly and almost scored in the opening minutes as prop Brad Dobson was held up on the line, but they did get on the board through Holmes' first penalty when Ilkley were caught offside.
Ilkley stand-off Saylor levelled with a penalty, but two more from Holmes gave YM a 9-3 half-time lead as both sides became locked in an intriguing arm wrestle with defences remaining intact.
Darrell McSwiney replaced Paul Gregson in the front row for the second half and YM gradually began to take the upper hand, finally breaking through on 48 minutes.
Skipper Mava Iosefa intercepted a short pass in midfield and broke through the attacking line before off-loading to Walker, who took play on another 35 metres.
With the cover closing in, he fed winger Holmes who took on and rounded his opposite number to go under the posts, making his own conversion a formality.
Ilkley defended doggedly, but YM stuck to their attacking guns, and unlike on some occasions when they have sat back, they were determined to close the visitors out.
The forwards drove on well and the ball retention was top drawer, and the Laund Hill men were soon over again.
This time prop Dobson set up the move with a 25-metre charge, sucking in defenders along the way, before the ball was worked to hard-working back rower Steve Anderson, who outstripped the cover and touched down near the posts, leaving Holmes another easy conversion for a 23-3 lead.
Another three points from Holmes after the visitors failed to release the tackled player and interfered with the ruck preceded two successive yellow cardings for Ilkley centre Vincent and open-side prop Cooksey.
Housley came on for Pearson, who picked up a knock to the knee, while Conrad Dent replaced Stuart Morton at centre, and Dent, with his first touch of the ball, scored his first-ever try for the club.
A superb show and go from stand-off Graeme Sarjeant carved open Ilkley's defence, and he linked with Iosefa, who in turn spun out a long pass to Dent, who outpaced the Ilkley wing to touch down in the corner. Holmes was unable to add the extras this time.
Ilkley threw everything at YM in the final minutes, but the defence held firm, and although Dent was yellow-carded for killing the ball, the home side kept their tryline intact in their best show of the season.
YMCA: Rees; Cowling, Morton (Dent, 75mins), Iosefa, Holmes, Sarjeant, Wolfe, Gregson (McSwiney 43mins), Guegue, Dobson, Hannan, Pearson (Housley 72mins), Bracken, Anderson, Walker.
Divisional results: Bradford Salem 25 Malton & Norton 12; Bridlington 6 Keighley 17; Scarborough 6 Pontefract 8; Wheatley Hills 17 Old Brodleians 20; York 23 Sandal 14.