does anyone have any knowlege about these .I've bought a smaller dia pulley and magnet from Australia for my twincharge project .the problem is the new magnet is 24volt, you get this voltage from a transformer (this may be a converter) supplied with the kit. when i energize the magnet the outer clutch cover slips , you can move it by hand when you put it back to the original 12volt magnet. with the same front cover it grips. anyone got any ideas , i don't want to give up on this