My first testing went bad!

[fastxturtle]

Ok I had the chance to run my SV today at a local lake and rolled it upside down twice. I manage to get the boat back thanks to currents. Once the boat gets rolling it goes pretty fast but it gets really unstable with little wake. How do you guys control this thing? Any solution for it roll over back to upright by itself?

[Meniscus]

What prop are you running?

[fastxturtle]

Everything is stock. And (2) 7 cell 4500mah batts that is about 7" CG from back

[jingalls007]

make sure your steering sensitivity isn't to generous, that will flip it real quick.

[fastxturtle]

yea i noticed that but how about rocking side to side at speed? I had to slow it down.....

[Darin Jordan]

Everything is stock. And (2) 7 cell 4500mah batts that is about 7" CG from back

That CG is WAY too far back... On a 27" hull, that's only 25% or so...

Forget what you think you know about the "proper" CG... Move the CG forward to 30%... maybe even more...

"Loose is fast" only counts if you can keep the darn thing upright...

[Darin Jordan]

yea i noticed that but how about rocking side to side at speed? I had to slow it down.....

Try this... Bend own the inside corner of each trim tab, about 1/4" in or so, down at a 45-degree angle... These "training wheels" will add a LOT of stability, with a minimal affect on speed. See the attached pics... The area in RED is the area you need to bend down.

Also... back to the cells... for racing... when the water gets choppy... the battery configuration shown in the second slide is what I use. It's not quite as fast down the straights, but it handles WAY better in the turns... so overall... I win a LOT of races like this... You have to finish, and it's not enough slower to make a difference if you are able to keep on it in the turns... I can throttle the whole course with this setup.... Thanks to Ken Haines for this tip... Might not need them so far in if you are using NiMH... The extra weight of those cells, however, way out to the sides... isn't helping your stability... When I was running NiMH, (6-cell packs), this is still how I ran them... just not quite so far fwd... See the second picture...

Hope this helps...

[Darin Jordan]

Of course... all this assumes you have the strut set correctly and the rudder caster set correctly... I run my strut neutral and my rudder slightly castered back... (bottom of rudder slightly behind the top)... Make sure you judge the strut angle using a straight-edge off the keel and NOT by the transom, as the transom isn't perpendicular to the keel...

[fastxturtle]

Thanks, Darin, I'll give that a try!

[Doby]

The SV is very tippy and does require some skill to keep it on its bottom. Its not known as the "Super Flip" for no reason!!

Keeping the bow down is a key part of the puzzle.

[Brushless55]

Try this... Bend own the inside corner of each trim tab, about 1/4" in or so, down at a 45-degree angle... These "training wheels" will add a LOT of stability, with a minimal affect on speed. See the attached pics... The area in RED is the area you need to bend down.

Also... back to the cells... for racing... when the water gets choppy... the battery configuration shown in the second slide is what I use. It's not quite as fast down the straights, but it handles WAY better in the turns... so overall... I win a LOT of races like this... You have to finish, and it's not enough slower to make a difference if you are able to keep on it in the turns... I can throttle the whole course with this setup.... Thanks to Ken Haines for this tip... Might not need them so far in if you are using NiMH... The extra weight of those cells, however, way out to the sides... isn't helping your stability... When I was running NiMH, (6-cell packs), this is still how I ran them... just not quite so far fwd... See the second picture...

Hope this helps...

Awesome stuff man!
So bend the trim taps towards the strut?

[brad65]

I'm having similar problems with the cg. I've set mine with my lipos all the way forward and about 8 1/2 cg. It runs very wet and never jumps out of the water. I've hit waves and nose dived which makes me believe I'm way nose heavy. I'm gonna try to move the batterys back like the picture Darin shows. I'm assuming this is another reason I'm not as fast as I thought I'd be running, my buddys nitro sv is keeping up with me LOL. Hope it helps.

[Steven Vaccaro]

Try this... Bend own the inside corner of each trim tab, about 1/4" in or so, down at a 45-degree angle... These "training wheels" will add a LOT of stability, with a minimal affect on speed. See the attached pics... The area in RED is the area you need to bend down.

Also... back to the cells... for racing... when the water gets choppy... the battery configuration shown in the second slide is what I use. It's not quite as fast down the straights, but it handles WAY better in the turns... so overall... I win a LOT of races like this... You have to finish, and it's not enough slower to make a difference if you are able to keep on it in the turns... I can throttle the whole course with this setup.... Thanks to Ken Haines for this tip... Might not need them so far in if you are using NiMH... The extra weight of those cells, however, way out to the sides... isn't helping your stability... When I was running NiMH, (6-cell packs), this is still how I ran them... just not quite so far fwd... See the second picture...

Hope this helps...

Thanks for posting that info Darin. I did that on my Syncron at the 2005 nats and it was night and day. The boat was smooth as silk when I did my testing, but once I ran in race water it was all over the place. turning down the inside corners really helped the situation.

[Darin Jordan]

Thanks for posting that info Darin. I did that on my Syncron at the 2005 nats and it was night and day. The boat was smooth as silk when I did my testing, but once I ran in race water it was all over the place. turning down the inside corners really helped the situation.

One the SV27 it's also night and day.... ON mine, it completely eliminated the chine-walking that normally occurs...

Now I just peg it and steer!

[fastxturtle]

Ok I did exactly what Darin told me to do and it works!!!!! It's like night and day the boat ran like a champ! I think i lost little bit of top speed and runnign time went down but maybe this is becuase the battery wasn;t fully charge last night, but it's very stable now even with the wake. I have lipos and S220 prop waiting for me and I can;t wait to set that up and test it. THX Darin!