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Old Oct 23, 2012, 03:55 PM
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Hi, Guys,
.
Great boat you have. Ah, another Mopar guy! Very cool.
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Old Oct 23, 2012, 08:44 PM
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Yup, is there any other?? ...thank you by the way !
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Old Oct 24, 2012, 11:03 AM
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Originally Posted by chidago View Post
Yup, is there any other?? ...thank you by the way !
I was actually thinking of painting mine in a mopar/cummins theme... looks like I will have to be more creative.
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Old Oct 24, 2012, 12:04 PM
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I was actually thinking of painting mine in a mopar/cummins theme... looks like I will have to be more creative.
It would be pretty cool to build a faux cummins motor for this boat. Throw a big and little snail on it and give it a nice vertical stack.

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Old Oct 24, 2012, 07:46 PM
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Vancouver, BC
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Originally Posted by chidago View Post
Thanks, Fire, I appreciate that..

This boat is such fun, but, we dont have the streams you guys have in BC, wish we did..

I have spotted 2, used em both, its a pleasure to be able to run it without the fear of it turning to junk..lol

I'm much more into fast gas, and sail, but, having had full size jets, this was a fun project, but, wasnt able to use any paint fancies..

I enjoy detail as well as performance..
Yes, we have a lot of water to play with up here, especially now that the rain has started again! A shame we might not be able to continue our hockey rivalry this year with this stupid lockout stuff going on.

How's your motor/esc combo holding up? I would have guessed that 3900kv on 3S would be a bit high, do you get cavitation or anything at full throttle?
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Old Oct 25, 2012, 08:03 AM
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I get a bit of cavitation above 3/4 throttle with 3200kv on 3s.
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Old Oct 25, 2012, 09:57 AM
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Yes, same here, but, Its always better to have more power than not enough, I put my mini cam on the boat, had chine wobble at speed, and because we here are making a short sprint course, I want the boat as stable as possible, I fabbed some home made trim tabs for it out of sheet stainless,
it settled the boat out well, and allows me to have some control over the nose dropping in a turn.. seems to work well, and as far as stream usage, they should'nt be in the way, I'm hoping..
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Old Oct 25, 2012, 12:20 PM
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kv != power... the higher the kv the less torque you have. Power is simply watts, which is volts * amps.

If it's cavitating you're not under as much load, and amps will drop off meaning putting less power to the water.
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Old Oct 25, 2012, 01:33 PM
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In my orange boat i have a 4300kv ezrun, but i programmed trottle trim on the tx at the limit of the drive.. so no to high kv related problems anymore.

But my hk500 2900kv outrunner with 700watts on the same tx/rx , same boat , same esc pushes way more water output though the drive. and no trottle trim, only full trottle!! :-)
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Old Oct 25, 2012, 04:45 PM
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Since these are soooo hard to find, I spent the time to source em out..NQD also make a bigger 21 inch boat, front motored, removable hatch, same jet..

Same company has the normal one also..the trading company and the factory are partnered up..

http://huayuantoys.en.alibaba.com/pr...e_RC_boat.html
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Old Oct 26, 2012, 11:13 AM
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Australia, NSW, Sydney
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I have just finished my Tear with a HK 4800kv water cooled motor and 35amp esc, I took it out for its maiden voyage today and am a little disappointed in its performance. I started off with a 1000mAh 2S battery and it wasn't that much faster than stock, so I put in a 3S and I was a bit faster but not blistering quick. I noticed that the steering nozzle is not submerged could this be the problem? Should I add more weight to submerge the jet?
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Old Oct 26, 2012, 12:08 PM
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Ayrshire, Scotland
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Originally Posted by Firehawk989 View Post
Yes, we have a lot of water to play with up here, especially now that the rain has started again!
I like the idea of a rainy season. Although we both live on the west sides of our respective countries there must be a difference between the Pacific and Atlantic Oceans. The only way we can tell it's summer is that the rain is not so cold
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Old Oct 26, 2012, 12:44 PM
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I have just finished my Tear with a HK 4800kv water cooled motor and 35amp esc, I took it out for its maiden voyage today and am a little disappointed in its performance.
Nozzle should not be submerged. Only the intake under the hull needs to be in the water. Of course

The performance will never be as fast as a prop-driven boat with the same motor/battery combo, so it depends what you expected. Blistering quick, as you put it, to me means over 50mph. The Tear jetdrive will never do more than about half that (which is still about twice what you could get away with for long in its natural habitat of rock filled streams).

That said a properly modded setup should be much faster than the stock boat but 4800kv is too much kv on 2s and swapping to a 3s battery will only make things worse. Look at all the posts on this subject by wparsons, firehawk et al over preceding pages. Your problem may therefore be cavitation.

Try taking it out again and see if it goes better on part throttle. Don't confuse noise at WOT with speed, in other words time it rather than depending on subjective sensation. If it goes as fast on 1/2 or even 3/4 throttle as at WOT then the problem is cavitation due to the kv of the motor. In that case get a better suited motor, because while running the ESC at part throttle to diagnose the problem is one thing, to do so for long periods is a recipe for disaster.
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Old Oct 26, 2012, 03:26 PM
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Originally Posted by nckmat View Post
I have just finished my Tear with a HK 4800kv water cooled motor and 35amp esc, I took it out for its maiden voyage today and am a little disappointed in its performance. I started off with a 1000mAh 2S battery and it wasn't that much faster than stock, so I put in a 3S and I was a bit faster but not blistering quick. I noticed that the steering nozzle is not submerged could this be the problem? Should I add more weight to submerge the jet?

1000mah probably can't give the amperage needed unless it's a 40c+ pack.

At a minimum I would suggest 18000-2200mah on 2s or 3s, and get higher C rated packs since it will draw a fair amount of current. I run 3s2200mah 30c in mine.
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Old Oct 26, 2012, 05:45 PM
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Originally Posted by wparsons View Post
1000mah probably can't give the amperage needed unless it's a 40c+ pack
Good spot! Although even if that is the immediate problem, then as soon as he uses batteries capable of giving the desired current I think he will find the 4800kv motor becomes a liability.
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