I put together a shockwave and it digs in something fierce on turns I bump the rudder as I enter the turn, let off, and throw HARD left to pull out of the turns!!! Any ideas Here's a vid to show ya what I'm talking about... Thanks Oz for the help loading videos



I thought ya see my setup as I walked by in the vid. I'm running a surface drive with an offset rudder. Pretty much the same setup as I've seen on y'alls boat. At slow speeds it doesn't do it... wide open, well you seen the results.

i had one (well still got it just dont run it any more)did the same thing.if i could see a pic. of the transom hardware i might be able to help ya

Will this do?

Where is your COG set at? If it is too far forward this can happen.

the pic. was great,thanks.what im going to tell you is what i did to mine and it did help it a lot.by no means im a pro at this for i am learning to.check your c.g. mine did best at 30% 16.5 from the transom.the rudder should be 2 1/2 from center of hull, i would say just behind the stringers but on that boat you have 6in stringers unless you moved them.the right trim tab has the water pick up in it for mine it caused drag.the leading edge of the rudder should be behind the trailing edge of the prop.the water pick up should be in the rudder(less drag). the prop looks dull, you should ballance it sharpen it and polish it.the 2 props that worked the best for me was a octura x472 and a x 670 both r 2 blades.check the strut it should be about 3/8in high from the center of the keel,also check the angle 0% to 1/2% should be ok.i used a dual rudder set up and it helped a lot but it had no water pick up in them. some will say a single rudder will be ok but i read in a book that a large boat(over 50 in)should use a dual rudder.i think top secert boats has a dual rudder set up with the water pick up in them.i used a spd system and made a water pick up in the rudder,it took some time but it did work. i think that should do it if you have any more questions please let me know and i will try to help ya. good luck steve (boatking)

Exactly 14" to back of transom The rudder I have on it has a water pickup already, so I'll shave the other one in the trim tab smooth. The rudder is in line with the rail, still at 6". I made my own motor mounts to fit. The only thing that is not set up like you said... the rudder is even with the prop not behind it. And I have the pitch kicked up about 1-1 1/2 degree to try and get the nose up. But even on a straight run, the bow doesn't get up out of the water. It's very small changes to get it set like ya said and try it. I'm running an prather 270 prop. Thanks for y'alls help... I see what it does this weekend.

Instead of putting anlge into your strut to get the bow up, try lowering the strut closer to the keel. This will make your hooking issue worse & will need the COG shifted back to counteract the hooking in the turn.

I have the shaft exit right at the bottom now... no way to lower any more.

As mentioned, the prop has to be sharp and balanced to start. That should be the first thing you do. You CG sounds way too far back at around 25%. I would shoot for 30% or so as mentioned also. Two things about the steering. 1: make sure you have a STRONG servo for steering and that the linkage is strong also. Normally a boat that carves hard in a turn and needs left to pull out is a sign of a weak servo and/or bending linkage. 2: you can try to make a strong/stiff extension for the rudder brackets to push the rudder back, so that it's leading edge is about even with the trailing edge of the prop. This typically works wonders on monos/deepvees. I had a similar problem with an Aeromarine XXX and solved the sensitive turning by doing this. You can read the article here on the site in the boat reviews section. It shows the extension I made for a similar rudder. Also make sure you don't have too much rudder throw dialed in on your radio...it doesn't take much to turn a mono at speed.

Run the stinger flat (parallel with boat's bottom) and adjust height to tighten/loosen up the boat. Again this was mentioned in a prior post. Good suggestion. Keep the trim tabs flat also. Make only minute adjustment to the right tab to use it to prevent torque roll if required. You do this by taking it down just a little bit. Remember trim tabs are basically like brakes if you lower them, you always try to use them as little as possible, dialing in only what you need to fine tune. Hope this helps.

Thanks Marc.. I thought about the linkage.. all good. 440 push rod with no bends, 1/4 scale servo, running a three cell lipo with 6volt reg. I can't move the rudder by hand. I have the strut coming out right at the bottom flush like you're saying, I just need to straighten out some. But by moving the cog up to 30%, won't that make it did in even more? The trim tabs have 1/16" of a gap from my straight edge, and the gap stays constant all the way to the trailing edge. I'm not having a torque problem, so should I adjust the right side down just a touch to keep it from digging in? Again, I thank all of you for your help!!!