I'm planing a surf trip to popoyos and all the close breaks and I was really wondering if a 4X4 is needed?
Depends on when you are planning to be here in Nicaragua. The rainy season starts up in mid-May usually and by say mid-June there will have been several good rains so the roads get pretty squishy by then.
The road to Popoyo is in good shape to Playa Gigante thanks to the Pellas' Guacalito de la Isla / Mukul Resort. The next few miles that are maintained well by Rancho Santana. After that though the road can get fairly bad, but not necessarily un-passable in a regular vehicle.
Hope that helps a bit. You might contact someone who lives down that way like at Magnific Rock or Buena Onda for more up-to-date information.
Let me know if you need first and/or last night's accommodation with airport transport near to Managua but not "in" Managua.
Mike @ Farmstay El Portón Verde
We were in Popoyo two weeks ago entering by way of the short cut at milepost 82 (+..5 km) and exiting along the Rivas road. We rented a sub-compact car from Budget and had no issues on these roads or other that were even less developed on the central coast. On the short cut road there is one creek/river crossing and it was not a problems. Small 2x4 trucks, motorcycles and buses were crossing it without an issue. We geared down mainly because of the banks on either side. The Rivas road was good all of the way. It is now paved half way to Gigante. The road from Playa Santana to Popoyo was a little rocky and less smooth overall, but there were no serious impediments. In the dry season I'd say a 4x4 is way overkill.