KennyN wrote:I also own a 7.4feet, 22 1/2, 51ltr fun board (see picture). I can sometimes just catch a small wave (haven't had the opportunity to try it in bigger waves yet), but even before I come on the flat part the board start to sink. I am sure a significant part of this is because of skills, but as the waves are often small it will be hard to improve these skills with this board only.
Therefore I am thinking of getting something in the middle. I don't have too much choices over here were I live but I can get a few NSP sups and surfboards models. One option I am considering is a 9.6 or 9.2 coco mat longboard.
You are sinking because a board needs to be planing across the top of the water to support your weight. On small waves that just cant happen unless you have a very big board/SUP. I've seen calculations that beginner SUPs for flat water should be a volume of 2X your weight in kg. Once on a wave, that can drop - but, in any event, a surfboard wont be anywhere near that size. Thus you need some speed
One thing to think about is where your board is weighted eg if you are starting to sink from the tail (tail goes down first) then you are too far back and need to move your weight toward the centre of the board (this might involve actually moving your feet). Your weight on the board will change all the time, front and back etc.
Another thing is whether you are going across the face of the wave (down the line) or straight toward the beach. If straight, then as soon as you are out of the push of the waves, your board will start to sink. So if you can go across the face, staying with the force of the wave, then you will get longer rides (obviously this requires a bottom turn of some kind, which is a skill development activity)
As to boards - either of those NSPs will be totally fine. Probably the longer one is better given your surfing conditions. For Bali, there are lots of boards around but remember transport and so on issues.
edit: just wanted to add a link to waikikichan's blog
http://alohaki.jugem.jp/?eid=610 you will see that they are surfing pretty small waves but are doing quite a lot on those waves. Probably most of the people are a bit lighter than you, but just to show that a good sized surfboard can make up for smaller waves. Also, the blog is worth a read anyway