tryed too lock it up at about 30kph a while back and got absolutely nothing , do they have some sort of cutoff or are they meant too be weak in the vs ?
It probably needs adjusting inside the rear discs where the handbrake shoes are.You can also adjust it at the handbrake cable,but it doesnt seem to get them as finely adjusted as when its done at the shoes.I adjust it at the shoes first,then finish it at the cable.Mine works excellent and will easily lock the wheels if pulled on while moving.