Fullback Karl Rees was again in the thick of the scoring action as he grabbed a brace of tries while Lee Thomas, Steve Richards and Terry Gurmin also crossed for the leaders.
Llanishen though, without a league win all season, did not lie down and claimed a four-try bonus point of their own through a penalty try and scores from prop Matthew Gee, fly half Gareth Bailey-Jones ad hooker Simon Furness.
Ystrad Rhondda and Mountain Ash remain in hot pursuit as they each recorded home victories.
Skipper Scott Davies and centre Garan Hill grabbed tries for Mountain Ash as they defeated Tredegar 20-9 and Ystrad Rhondda have still only lost one league tie all season after their 18-9 win at home to Ynysybwl.
In Division Three East, Abergavenny and Brynmawr are locked on 54 points apiece at the summit after they each recorded away victories, Abergavenny downing Nelson 20-12 and Brynmawr overcoming Pontypool United 19-6.
Bedlinog were made to fight to keep their unbeaten record in Division Three South East alive as they scraped past Llantwit Fardre 12-11, while in the chasing pack Gilfach Goch recorded a 38-29 victory over Fairwater and St Peter’s leapfrogged Treorchy in the table after beating Tylorstown 25-11.
Llandaff North secured another bonus point win in Four South East as they ran five tries past Dowlais in a 35-13 win and second placed Aberdare were also winners, 23-15 at home to Cefn Coed.