I bought a new Severne NCX sail 7.5 from 2023. I paired It with a Severne blue 460 SDM last but i have a problem. When it s rigged it s difficult to pass the battens. I have to force. I changed dowhaul tension, outhaul tension and batten tension with no improvement. Is anyone had the same observation ? Do i need a rdm mast ? Thanks

Not sure what you are after, the tip of the battens (at boom height and below) should usually be on the side of the mast when there is no wind in the sail (these sails are also referred to as RAF sail). Once the wind fills in, the battens will automatically be pulled more behind the mast (from either side of the mast) and give the sail it profile. The battens don't really need to "pass", unless you are trying this on land with out any wind in the sail.

Karo has a video on the tuning, you can see how the battens are resting on one side of the mast when there is no wind in the sail:

Thanks for your answer. But even on water the battens are not pulled enough behind the mast and i need some effort to pass the battens after a gybe or a tack

NCX can be rigged on SDM or RDM. If you apply enough downhaul, the battens should work. My guess is that you don't have enough downhaul. Show us how it's rigged by posting a photo.