Opener Tinashe Gomwe struck 11 sixes and 17 fours in an outstanding innings of 165, sharing an opening stand of 181 with Rashid Ayub (78).
Skipper Adrian Monk then scored a quickfire 55 and overseas all-rounder Israr Ullah 33 as Saltaire reached a massive 354-5.
Windhill were bowled out for a mere 68, with Adeel Ashraf taking 5-26 and Mohammed Munir 4-11.
Skipper Simon Bailey (4-53) and Waqas Maqsood (4-69) each took four wickets for Baildon, who were restricted to 175-9 in reply, with Bailey making 35 as young spinner Amit Hussain took 3-54.
These results leave Undercliffe on 283 points, 41 ahead of Saltaire with third-placed Keighley a further 25 points behind.
Windhill are 31 points adrift at the bottom.
There was a close finish at Brighouse as the home side went down by four runs against Great Horton. Naeem Khan scored 83 not out to help Great Horton reach 183 as Tahir Khan took 5-36 and Umar Salim 4-30.
Mohammed Rafiq (33), Zafar Jadoon (33), Mohammed Rafiq (33) and Umar Salim (32) all made useful contributions but next-to-bottom Brighouse fell just short of their target, with Samad Rehman taking 3-22 and Sadaqat Zaman 3-44.
Gomersal beat neighbours Spen Victoria by seven wickets. Spen made 191-9, with George Deegan and former Gomersal captain Rob Burton (30) their top scorers.
This total presented no problems to Gomersal once openers Graham Hilton, with 85 not out, and Adam Greenwood (59) had put on 107 for the first wicket.
Outstanding bowling by Mohammed Zahid (5-11) and Wajid Hussain (5-32) enabled Idle to beat Bowling Old Lane by 91 runs after bowling out the home side for 102.
Idle owed their total of 193-2 to steady batting by William Sharp (59), Simon Curry (47), Nik Cumming (43 not out) and Chris Wynd 43.