Tohatsu 12hp Help

[jsbill50]

I have a mid 80's 12 hp 2 stroke. It starts well, idles nicely but will not rev to get the little Aqua Lark I have it on to plane. If I hang myself way over the bow and push the nose down it sometimes will begin to rev and run beautifully at Wide Open Throttle. I recently put new pistons and rings in it and compression is around 135 in both cylinders. Any ideas why it won't rev to get the boat on plane?

 

[pvanv]

Trim and pitch. Parts are NLA, so enjoy what you have.