Lloyd banged over six goals in atrocious conditions at the Groe as the Bulls shrugged off an early 19-0 deficit to beat the table-toppers 26-22. Forwards Ben Duggan and Gareth Kinsey scored second-half tries for the home side.
Team manager Justin Lewis said the victory was perfect preparation for his side's Konica Minolta Cup quarter-final match at Pontypridd next Saturday.
"We were 19-0 down after only 10 minutes, but we had chosen to play into the wind in the first half and that paid off," he said.
"It wasn't a day for the backs, so in the second half, we knew we had to keep it in the forwards and keep driving it up the middle. We've missed Rob Lloyd for the last three games, because he's a Marine and he's been away, and his kicking was crucial.
"We said before the game that we could win this one, and we knew it would give us a lot of confidence ahead of playing a Premiership side at Sardis Road.
"This season is strange - we can produce this sort of performance against the good sides, but can't seem to do it against the poorer sides."
Despite the loss, Bonymaen are still warm favourites to finish on top of the league. Their nearest rivals, Beddau, had a royal chance to narrow the margin to two points but crashed 31-13 at home to fellow title contenders Newbridge.
In another game decided by the wind, Beddau led 13-11 at the break, only to concede second-half tries to forwards Chris James and Chris Payne. Newbridge outside-half Greg Jones added 16 points with the boot.
Cwmllynfell continued their fine season with a 23-15 win at Caerphilly, with Neil Thomas, Paul Davies and Jim Morgan scoring tries for the visitors, while Merthyr ran in five first-half tries in their 27-10 victory over Narberth.
Waunarlwydd shut out Fleur de Lys 15-0, with a try double to Ed Bennett, and Blackwood found their feet in the second half to come back and beat Llanharan 20-15.
Fourth-placed Whitland spurned a chance to climb the table when their home match against bottom-placed Ystrad Rhondda finished in a rare nil-all draw. The mid-table Llangennech-UWIC match was abandoned at halftime because of torrential rain. Llangennech were leading 7-5 at the time.
Wales 7s Manager Steff Thomas believes Luke Treharne has all the attriubutes to be a top class captain. WRU TV's Graeme Gillespie hears his reasons why as the squad prepare for the opening two legs of the new World Series in Dubai and South Africa.
The British & Irish Cup kicks off this weekend with the four Regional Premiership Select XVs flying the flag for Wales. Welsh
Sat 14 Nov: Blues Premiership Select v Nottingham (2.30) & Connacht Eagles v Dragons (2.30)
Sun 15 Nov: Yorkshire Carnegie v Ospreys Premiership Select (1.30) & Scarlets v Bedford Blues (3.00)
The Welsh Rugby Union is forming a new Youth Board with a brief to help keep more young people involved in the game during their late teenage years and beyond. The first task of the fifteen strong Board will be to analyse and consider the issues which lead to a number of youngsters drifting away from the sport between the ages of 16 and 21. To apply visit www.wru.wales/youthboard
The Foster's Challenge Cup will involve the 12 Principality Premiership sides and will run during European and British & Irish Cup weeks, providing vital fixtures for the participating clubs and an opportunity for upcoming players to step up to semi-professional rugby and make a claim for starting places within the Premiership squads.
Eighty schools and colleges in Wales now have a full time rugby officer as part of the WRU's school club hub scheme. All of the school club hub officers recently gathered at the National Centre of Excellence for various workshops.
With Liam Williams forced out of the World Cup through injury, lock Luke Charteris and Skills Coach Neil Jenkins say they have to put yesterday's defeat behind them as Wales now look ahead to another physical encounter against South Africa in the quarter-finals of the Rugby World Cup.
WRU Consultant Head of Physical Performance Paul Stridgeon praises the Physical Performance department for their work and dedication as he addresses the media ahead of Wales' Pool A clash against Australia
Twelve young people have been selected to follow a one year WRU Coach Core apprenticeship programme. Coach Core was set up by the Royal Foundation of the Duke and Duchess of Cambridge and Prince Harry as part of the Olympics legacy in 2012 and the Duke of Cambridge was on hand to meet the apprentices on their first day in the job. The programme has been funded by the Hunter Foundation.