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Author Topic: XRAD'S King of Shaves 58"  (Read 1198 times)

xrad

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XRAD'S King of Shaves 58"
« on: July 22, 2017, 03:32:22 pm »

Bought this a few months ago. was gas, converted to electric.

5692 Leopard 2000kv motor
x4 4s packs 100c discharge
prather 270 prop
400amp esc water cooled
Garmin GPS

top speed first run 55.49 mph (89 kmph)

Tried a few other prop sizes and blade number combos.  The 270 balanced/polished  was very good compared to others. Motor timing at 0 degrees.

video:
https://www.youtube.com/watch?v=iXLHvC1I8_o&t=3s



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martno1fan

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Re: XRAD'S King of Shaves 58"
« Reply #1 on: July 23, 2017, 12:14:03 pm »

You sure its 2000 kv ? thats a lot of kv for a large gas size boat,most go for much lower kv ,no way that 70 mm prop is going to work well on such a large amount of kv on 8s thats a possible 49 k rpm loaded 59 k rpm unloaded thats going to create masses of heat and burn thing out pretty dam quick especially with a large prop.
Usually with a large boat like that on 8s with a higher rpm youd be best using a much smaller prop in the 60+ mm range to allow the motor to spin at optimum rpm but as i say thats too high a kv rating for a large boat . You should be aiming for rpm range of nearer 30 k on a fast electric but using smallish props.To use that large prop youd be best with lower kv and less rpm to be able to use gas size props.
The most KV id use on a large boat is 1000 kv and even thats not ideal,thats what im using in my 58 Apache but as i say its not ideal ,just what i had lying around lol .You def need to use smaller props to allow the motor to rev out but as i say im worried about your chosen setup .
Heres one of my 50" cats done as twin electric , speeds similar to yours bit faster actually but hes only using small outrunners on 6s each and there 1250 kv i think which is perfect for 6 s using 57 mm props .If i were you id be trying smaller props in the 60+ mm range .Theres a gas size cat the zelos which is a bit smaller she uses 1000 kv motor on 6-8 s and small prop and runs pretty well.Your prop for your setup is too big imo .If i were you id try something around 65-67 mm.Might sound small but when its spinning at high rpm it should do much better than that large prop thats bogging you down.
https://www.youtube.com/watch?v=veLDws6bc24&index=5&list=FLBvMrXd-byRavNCBWuCxqHg
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martno1fan

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Re: XRAD'S King of Shaves 58"
« Reply #2 on: July 23, 2017, 12:26:42 pm »

This one has the 5698 motor 910 kv on 8s 1 pack hes using a small 52 mm prop,bit too small in my opinion but you can see its moving much faster than yours as the motors reving out better .

https://www.youtube.com/watch?v=dHwl96iZ5t4
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xrad

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Re: XRAD'S King of Shaves 58"
« Reply #3 on: July 23, 2017, 11:10:43 pm »

Not 2000 kv....that's my other build.  It's 1340kv. Yeah, I know about the prop size, using what I have in the box.  Was my smallest 2 blade 1/4" prop. Will try 60 something in a few months.  Still 55+ first run on choppy lake is not bad.  And this boat is 8" longer than the Thunderbolt. Need better batteries. Old batteries not holding charge anymore. Running 8s2p (made out of 4x4s) ~29v.  Motor barely warm after run.   esc barely warm.  batteries not so good...

As you can see, she is just rigged up for a few runs with zip-ties.  Beer was more important that day.  Handles fairly well, very steady on straight ways....
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martno1fan

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Re: XRAD'S King of Shaves 58"
« Reply #4 on: July 24, 2017, 10:07:08 pm »

King of shaves is longer but has a bigger overhang ,the sponson ride surface however is not much longer  plus the Thunderbolt is 2 " wider .
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xrad

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Re: XRAD'S King of Shaves 58"
« Reply #5 on: July 25, 2017, 12:05:49 am »

Martno, I can only find one (small than 70mm) 67mm prop for 1/4 shaft (by Octura)...do you have source for 65/63/60 etc with diff pitch?  I am not going to use adapter, but I may put smaller flex shaft in as last resort....
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martno1fan

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Re: XRAD'S King of Shaves 58"
« Reply #6 on: July 25, 2017, 08:12:10 am »

Martno, I can only find one (small than 70mm) 67mm prop for 1/4 shaft (by Octura)...do you have source for 65/63/60 etc with diff pitch?  I am not going to use adapter, but I may put smaller flex shaft in as last resort....
Yea what you need is a 1/4 flex and shaft that steps down to 3/16" that way you can get the props you need .
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