Hello all, so after a long & helpful discussion on the "M section discussion group"
https://www.facebook.com/groups/679193992180229/ (M section is a reference to NAVIGA's section reference for motorized models)
The chaps on there were very helpful and not at all condescending even thou my video of my first test left a lot to be desired!
So here's the list of what has been suggested I change;
1. change the motor from a 36mm can to a 28 or 29mm as the 36 has way to much torque which just flips a lightweight boat like this one.
2. move the servo nearer to the transom to help with reducing any flex or flop in the steering.
3. test the servo for "glitching". I've done this, it does twitch at full power so I will be replacing this servo.
4. replace plastic servo arm with an aluminium one.
5. replace or strengthen the rudder linkage to reduce flex
6. move the center of gravity to 28% of the hull length from the transom (195mm as apposed to the 220mm which I have)
7. angle the bottom of the rudder forward by 1 degree to help keep the bow up (I inadvertently had it 1 degree the other way which would contribute to keeping the bow down and therefore digging in during turns)
8. replacing the swept back turn fin (apparently this style is mainly used on riggers and cats again to keep the bow down, I used it 'cause it looked good!) with a square fin.
9. move the "kill loop" from the transom to the top deck as some if not most clubs would not allow this configuration to compete. I had only put it where I had because I had seen it on another boat & thought it looked neat!
10. and of course finally fill & make-good the scratches it had received jumping out of the lake! (I know it will likely get more during a season but you might as well start tidy!)
This should keep me busy for a while, I'll post pictures when complete then have another go at testing!
P.s there were other suggestions, but these made the most sense and seamed a lot more practical to complete.
In the North;
http://www.ampdraggers.co.uk/In the East;
https://ostendospreys.wordpress.com/In the South;
http://www.electrafying.com/ &
http://shpowerboats.co.uk/In the West;
http://www.swambc.webeden.co.uk/#/swarm-home/4581722394