Do i need a lead free reducer for my fuel filler to meet SVA requirements? I have a medium size Aero cap fitted without a reducer at present, if so what do i use?

Depends on your engine year but it shouldn't be a problem go to the scrappies and get the filler neck off say a 95 Rover 214 trim it down and alter it to fit it inside your existing filler neck.

Also I am told a lot of SVA testers are looking for lockable fuel caps -- even a lockable flap isn't good enough.

The reducer doesn't have to be lead free... the reducer is there to stop you inserting the lead free fuel nozzle. Sorry, couldn't resist!!!

We simply used a piece of aluminium sheet with a (IIRC) 22mm hole through to fit inside the existing filler orifice...

I've even heard of some people dropping a huge washer into the neck ...... it stopped the leaded filler nozzle going in so it passed SVA!!

Funny enough it seemed to have dropped out somewhere on the way home