Gai Waterhouse believes the handicapping system is foiling her attempts to win a sixth Epsom Handicap at Randwick on Saturday.Sydney's premier trainer says Rock Kingdom on 52 kilograms is much too close to better-performed rivals such as triple Group One winner Mentality who has 55.5kg ahead of Wednesday's declaration of the final field for the prestigious Randwick "mile".Weights will have to be raised with the defections of the original topweights and if Mentality starts he will carry 57kg."It'

Gai Waterhouse believes the handicapping system is foiling her attempts to win a sixth Epsom Handicap at Randwick on Saturday.

Sydney's premier trainer says Rock Kingdom on 52 kilograms is much too close to better-performed rivals such as triple Group One winner Mentality who has 55.5kg ahead of Wednesday's declaration of the final field for the prestigious Randwick "mile".

Weights will have to be raised with the defections of the original topweights and if Mentality starts he will carry 57kg.

"It's a joke, the handicaps are screwed," Waterhouse said.

"Why they work on a 52 (kilogram) limit is beyond me.

"Rock Kingdom is a rising star who has come through his classes and Mentality is a Group One winner so why are they so close.

"There should be more of a sliding scale, it's not right and they seem to have a better spread of weights in Melbourne.

"They seem to base everything on the weight-for-age scale but horses should go through their classes, then to handicaps and then to weight-for-age.

"The system at the moment is buggered."

In saying all that, Waterhouse is happy with Rock Kingdom who is at $12 on TAB Sportsbet with Rangirangdoo the $3.80 favourite ahead of Drumbeats at $5.50.

Surprise George Main Stakes winner Road To Rock from the Anthony Cummings stable has firmed to $6.50 following his win.

Rock Kingdom finished eight lengths sixth in the George Main (1600m) following his first-up second to Racing To Win in the Theo Marks Stakes (1400m).

Waterhouse's Epsom Handicap winners so far are Iron Horse (1997), Excellerator (2002), Desert War (2004, 2005) and Theseo (2008).

Iron Horse carried 54.5kg, Desert War 50.5kg for his first win and 56.5kg the following year, Excellerator had 53kg and Theseo 51.5kg.