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View Full Version : Stock King of Slaves, I mean Shaves.


vasy
06-13-2010, 01:43 AM
Quick intro:
A friend bought a king, put a 3 cell into in and it smoked the motors.
LHS agreed to replace the boat with a brand new one and deal with Venom directly for the motor replacement.
Owner of the LHS liked the boat and when the guy replaced stock motor with 10xl and hobbywing ESC (http://forums.offshoreelectrics.com/showthread.php?t=15166) took the brand new stock motors and ESC back to be used in the burned boat as he just liked the way it looks.

So after reading a few posts here and there and taking all of the suggestions on the stock setup we removed the motor bolts and reinstalled them adding extra washers and lock-washers to make sure they were no touching the motor windings inside. (what a pain that was)
Did all the adjustments and let it rip today with all stock hardware.

It went through 2 sets of 3300 3cells 20c and one set of 3 cell 5000Mah 40c with no issues. Motors were cool to the touch and no other problems.
Then he decided, ah whatever, if the motors burn, so be it. He put the 4s 40c batteries and let it rip and rip it did. It was really fast and stable on the water with props set at -2 degree just flying over-top of little waves.
Did 1.5 minute test run and brought it in.
Motors and esc were cool to the touch, I even stuck my finger as far as I could from the back and it was barely warm.
So maybe you guys had it right about the boat catching fire because of the damn motor screws?

I'll keep you updated as I'm sure he will run a few more full 4s packs next time and we will see what happens. He also added stoppers to prevent lost flex cables. He lost one last weekend almost right away so we were not able to do any testing.

One weakness we found is the rudder mount, if you flip the boat at full tilt is bends. The metal, or should I say tin, is very thin and bend rather easy during mishaps, also be sure to rip the servo mount and re-glue it with epoxy or whatever, they did not use enough glue.
ray schrauwen
06-13-2010, 02:48 AM
Nice post, thanks!

When I checked Darla's motor, there was maybe some indication of this problem. Without a magnifying glass or microscope, not 100% sure.
C-Mac
06-13-2010, 11:05 AM
I agree with you on the rudder mount. I flipped my EKOS a couple times yesterday in chop and when I got her back the rudder was all bent.
VIKOS
06-13-2010, 04:12 PM
Really I cleared out the water backflipped and kept going landed on the rear of the boat. No problems at all. Hmm but I do gave a spare rudder and parts so guess if it happens it'll becalright.
vasy
06-13-2010, 10:04 PM
So we GPSed the stock on 3s and after on 4s. The water was a bit choppy so it can probably go a bit faster but that is what we had to deal with.
3s was 48km/h or 29.8mph
4s was 68km/h or 42.3mph

It was a bit windy so will run a test again next weekend, hope for a bit calmer conditions.
Man, what a difference that one extra cell makes :)
ray schrauwen
06-13-2010, 11:26 PM
What props?
vasy
06-13-2010, 11:44 PM
What props?

What ever the stock black plastic prop is that comes with the boat..
VIKOS
06-14-2010, 01:51 AM
thats a 36mm and I told you you where no where near 35 on stock set up lol...thats a big jump just on 4s alone..you mean one more cell makes that mph jump to close to 45 mph I doubt that..what kinda gps you using. and a 10 mph difference just from a battery change...wonder what aluminum props would do since the plastics tend to flex alot..
vasy
06-14-2010, 02:00 AM
thats a 36mm and I told you you where no where near 35 on stock set up lol...thats a big jump just on 4s alone..you mean one more cell makes that mph jump to close to 45 mph I doubt that..what kinda gps you using. and a 10 mph difference just from a battery change...wonder what aluminum props would do since the plastics tend to flex alot..

Garmin, forgot the model will have to look it up.
As I said, the weather was not the best for true readings. We did the run on 3s and 4s with in maybe 10 minutes but wind has changed. I'd not call them consistent and repeatable readings at this point. Water conditions make for a huge difference, I'd love to test both back to back on the calm day but on 4s the boat was for sure noticeably faster by a fair margin.
Will try to make a video next time, hope someone will bring a camera and post on youtube after.
VIKOS
06-14-2010, 08:58 PM
Hmm mght have to try 4s lol who cares if motors blow lol I want to see it run.
Rumdog
06-14-2010, 09:07 PM
Well, if the motors go, so can the esc's. They can easily destroy your hull, and cells when that happens. i'd think twice about it.
vasy
06-14-2010, 10:25 PM
Well, if the motors go, so can the esc's. They can easily destroy your hull, and cells when that happens. i'd think twice about it.

Depends what goes 1st :)
I've seen motors burn in this hull, and I mean burn to the point that solder was on the bottom of the hull and the 3 motor wires fell off the motor and the green colour faded away, just a bit of foam in the cowl melted.
Have not had ESC failure yet in this boat, but they seem to fail with much more smoke and fire going by another boat i had this happen in.

I'll measure the amp draw on the weekend with 3s and 4s will update on the loads. I honestly think motor/bearings will go before the ESC but your millage might be different :)
With stock props I don't see it taking more then 60amps considering that on 10xl with 4s and 40mm props the most I've seen was 72amps and that was a spike.

The most we have done is about 2.5 minutes running WOT one way down wind and then returning at 1/2 speed to prevent flip-over and esc was cold to the touch. Did maybe 10-15 passes in that 2.5 mins but I was not really counting and that number is guess. It was for sure more then 5 :)
I only had 4s 2200 to lend the guys for a test and that is all the time they can take, came back with 3.69v per cell.

I'll keep you posted... the owner is not overly concerned about smoking the ESC or the motors so he will push it to the limit.
VIKOS
06-15-2010, 06:19 PM
Nor am I either. But like stated the bearings in the motors could go before anything else goes. Especially with mine being a Lil stiff to turn till I sprayed them.
VIKOS
07-02-2010, 06:52 PM
Sorry to say stock set up props suck on 4s. They kept sheering once the boat got airborne from a lil chop. Must be glassy water if ur Gona try 4s on stock props. Other wise use metal or aluminum for strength indeed. Boat test in about 13 hours if not later.