Spartan, tear it down to build it up

[GeoVW72]

Hey Geo, what motor and prop were you using to get those numbers??
thanks!!

Still stock motor and prop.

Motor's got very little life left now, got to 180*f after sitting for 2 min, was 160* when I pulled it out. The whole temp sensor "fail safe" is kind of BS.
Changing the stuffing tube is actually good for 2-3mph on 4s, ~33mph, but cleaning the hull and the tabs got an extra mph out of it.
Getting up to 50 takes a lot of space though, I'm guessing even more with a dirty hull.
With the new cable I could see the 50+ on the box.

Got a Photo in the paper again, at least its for the right reasons. Most will be happy to know that I have no decals on the hull, so no one knows what it is. The lake that pic was taken at is pretty big.

cable's on the way

[GeoVW72]

Got the cable

If nothing else I'll say I can get consistent numbers

34 on 4s


50 on 6s


But the "Flutter" happened again, motor was already on the way out though.
Some how the tray came loose too and the drive dog was on the strut, so that was a contributing factor.
Cable didn't have much grease on it, but what was there wasn't nasty black, grease on the liner was discolored, but I didn't hear the liner spinning excessively like with the stock cable.
Drive line temps were still hot in my opinion, 140*f, motor toasted at 210*, but the fail safe would not have done anything as the "temp" was 145*
Perhaps motor alignment is an issue, just have to keep at it.

Chine walking is pretty much gone, except later in the run when the drive line heated up , and rather minimal. It will still do it if it hits a wake the wrong way or you get on it too quick. Not sure if the trim tabs are the fix or not, amp draw is higher than before but that may just be the motor.

I'll have to try it without them and see what it does, after I get a motor

[GeoVW72]

Well, make a franken motor by taking a Feiago 540XL rotor and putting it in one of the Traxxas cans. Fit OK, not a true 1:1 replacement, but it works.

This isolates the "fluttering" fault 100% to the rotor de-magnetizing, not the esc or anything else. Other failures can be attributed to defective units or continued use with the fluttering/cogging issue which puts an extremely high load on the esc.

Removed all the trim tabs and the boat still ran perfectly other than the usual occurrences that caused chine walking; running over own wake, getting on it too quick.

Speed was lower, but so was amp draw;

4s:
down to 31 from 34mph
amp down to 50 vs. 60A

6s:
down to 47 from 50
amp down to 90 vs. 130A

Batteries in the same position; rear for 4s mid on 6s
Strut and the same level setting.
rotor/motor may have been weaker

I think that the speed may have come from how cleanly the water leaves the boat, squared tabs vs. curved plastic. Boat seemed to ride higher out of the water without the tabs. I may have not adjusted the tabs correctly, try, try again.

Drive line was again excessively hot in m opinion, 150*f. Very little grease on the flex shaft, but what was there wasn't dirty or discolored. I did not lube the exterior of the teflon, which was matted, indicating that it was spinning, but there were no teflon flakes. Interior was fine and the piece of water line over the cable and tube was still there and not a blob of molten goo.

The drive line seems to be the only thing that heats up to change the amp draw, from 90A to 150A at failure (log file didn't save correctly)

Seems obvious, the drive line is the root of all this, back to the drawing board

[Doug B]

Im not real experienced with boats, and the driveline is very different than anything I am used too (not counting old speedos and tachs.. ) so I have questions..

Are most boats that use a cable drive straight, or do the all have some bend in the stuffing tube?

Are there any similar boats that work well with the 1/4" stuffing tube / .150 cable setup? If so, are there any notable differences in the system?

Why arent boats using a "solid" drive shaft, with a CV coupling to make the bend? seems that would work better and create zero heat and zero loss from friction.

[Brushless55]

Hey Geo, what kv is that XL motor?

[dag-nabit]

Im not real experienced with boats, and the driveline is very different than anything I am used too (not counting old speedos and tachs.. ) so I have questions..

Are most boats that use a cable drive straight, or do the all have some bend in the stuffing tube?

Are there any similar boats that work well with the 1/4" stuffing tube / .150 cable setup? If so, are there any notable differences in the system?

Why arent boats using a "solid" drive shaft, with a CV coupling to make the bend? seems that would work better and create zero heat and zero loss from friction.

Pretty much all stuffing tubes have some sort of bend in them. You can't mount the motor horizontally in the hull low enough for the stuffing tube to exit straight out the transom.

So the stuffing tube is curved to compensate for the angle the motor is mounted at, and allow the stuffing tube to exit parallel (horizontal) with the bottom of the boat.


Based only on my hands on experience, we have a couple SV27's with similar stuffing tube/drive cable set up. They are into their third season on the water with zero drive line problems.

On the SV's the stuffing tube comes in relatively flat until just before the motor, then it curves upwards. If anything the angle is more acute than the bend in the Spartan stuffing tube, and still no problems.

Kevin

[GeoVW72]

Doug B: cables are used to get the rotation in line from point A to B same as speedometer cables, were just putting lots of power through them.
Almost all the drive lines I've seen have some bend to them, some seem really extreme.

Pro boat uses 1/4" brass and .150 cable similar to the Spartan's cable in most of their models without much issue other than the occasional unraveling. However they are only running on 4s with a 1500kv motor (22,000rpm vs 35,500 on 6s with the Spartan)

Most don't use CVs, universals, or gears because of the amount of torque required to turn the prop, Pro boat has a few models with solid drive shafts, but they are more light sport boats.

BL55: it was a 1668kv, but I was using the rotor from it in the stock can. The magnets are 1:1, but the shafts are different.

None the less, it burned up just the same

dag-nabit: Agreed, the Spartan definitely has a large drive line issue



Things to work on waiting for parts:

Brushed Spartan:

removed the 775 torque ring to aid in cooling, may as well see what it does, chucked the burned one and got a slightly used one off a friend after I built his Monster Summit.

Villain VX(EX=EVX -V, so VXL - the L):

Still hops on 2s with x447s, lost the hatch, so have to track one down.

[GeoVW72]

1717 Spartan

Ran the brushed spartan, but forgot the eagle tree

Seemed faster, but after just 3 min on the stock prop the motor was at ~120*f. Maybe too hot, at least in my book. Jacket didn't leak though.

Spartan 1717: I am hoping to do a "Monster" spartan at some point, when I can get my hands on a white hull.
Executed on 3/3/11 while waiting for stock parts based on the public "will X fit"

using a rigged ICE 160HV, amp draw on the stock prop is similar to stock components, but the speed was a little less. never went much beyond that.

Everything was a pretty tight fit, but the ICE chassis fits perfectly in the tray


I plan on working with it some more after I get the stock components to work as they should.
YT Vid

My guess on the new Castle Traxxas marine is that it will be like the E-Revo Brushless editon, most likely with a hydra ICE 120 or 180 and 14 series motor as they're coming with 5mm shafts now.

Still working on the drive line issue, anyone wants to see the misalignment I'm talking about, just remove the tray from the boat and move the transom end of the stuffing tube down and watch it flex where it's bolted to the tray.

Until then

[mtnbiker94]

I keep hearing about problems with the flex shaft and everything not being aligned properly, and things getting discolored. I just recently got my spartan so I'm fairly new to all this. How do you know when it's time to replace the stuffing tube and flex shaft, because I have an extra of both? So every time I run my spartan I pull out the flex cable, clean it up and lube it. It does have some discoloration, and the grease(aquacraft grimracer grease) comes out a pretty nasty color brown. Is it time to replace everything??

Thanks alot guys

[Brushless55]

Ran the brushed spartan, but forgot the eagle tree

Seemed faster, but after just 3 min on the stock prop the motor was at ~120*f. Maybe too hot, at least in my book. Jacket didn't leak though.


Until then

120* is ok bro
200* could be an issue

[GeoVW72]

I keep hearing about problems with the flex shaft and everything not being aligned properly, and things getting discolored. I just recently got my spartan so I'm fairly new to all this. How do you know when it's time to replace the stuffing tube and flex shaft, because I have an extra of both? So every time I run my spartan I pull out the flex cable, clean it up and lube it. It does have some discoloration, and the grease(aquacraft grimracer grease) comes out a pretty nasty color brown. Is it time to replace everything??

Thanks alot guys

The grease will always come out nasty with the stock cable, just the way it is.
the discoloration usually occurs on the brass of the stuffing tube.
The part you have to watch for wear is the teflon liner in the brass, other than that run it till it brakes or the cable looks damaged, ie unwinding.

As far as alignment:

I am working hard to get it right and feel it should be attached to the tray at another point to take the flex out.




The nice thing about K&S tubing is that the next size up fits snugly on the smaller one. 9/32" onto 1/4"
All that is required is that the rear guide be clearanced for the larger tube, which is then epoxied in to the correct alignment and then the bend is created past that.
I would still NOT call this done as the drive line temps still seem hot(125*f) to me.



I used styrene tube to fill the gap between the strut and transom and there still wasn't a good coating of grease on the shaft after a run. I'm still thinking that it's auguring out some how given that no suction is present.

Still at it

[dascoadams]

I know its off subject but Are the Spartan factory adj. trim tabs the only ones that fit...without mods

[GeoVW72]

I know its off subject but Are the Spartan factory adj. trim tabs the only ones that fit...without mods

Nothing is off topic as long as it's spartan related
Some have used Supervee 27 tab adj from Kintec, I don't really feel they're necessary but they make good transom bling.


Hope everyone had a fun, safe 4th, didn't do much spartan related because I knew the parts were on there way.

Deconstructed Here

Took a few steps back to evaluate the how effective the new motor is:

Standard series cooling loop, stock stuffing tube and drive shaft. Stock jacket is useless so I didn't even bother, rest of the cooling mods are intact.

Super aligned drive shaft didn't change much, but I'm still working on a few other ideas.
A few drops of CA/super glue at the end of the brass where the teflon is will keep the liner from spinning though and allow the teflon to be removed relatively easy once it is worn or damaged.

More once it gets wet

[dascoadams]

I have a set of the sv adj. Trim tabs..and they take quite a bit of modification to fit...and it is mainly for the bling...lol...thanks man

Nothing is off topic as long as it's spartan related
Some have used Supervee 27 tab adj from Kintec, I don't really feel they're necessary but they make good transom bling.


Hope everyone had a fun, safe 4th, didn't do much spartan related because I knew the parts were on there way.

Deconstructed Here

Took a few steps back to evaluate the how effective the new motor is:

Standard series cooling loop, stock stuffing tube and drive shaft. Stock jacket is useless so I didn't even bother, rest of the cooling mods are intact.

Super aligned drive shaft didn't change much, but I'm still working on a few other ideas.
A few drops of CA/super glue at the end of the brass where the teflon is will keep the liner from spinning though and allow the teflon to be removed relatively easy once it is worn or damaged.

More once it gets wet

[Doug B]

my .25 on the grease thing- it will absolutely auger the grease, its pretty aggressive about it in my opinion, if you put a thumbnail on the cable and spin it in the direction of normal rotation your nail travels rapidly down the cable.. like a course thread bolt.. if at any point during use it balloons a little bit (high rpm or abrupt decel perhaps?) its going to act like a meat grinder, forcing everything out double speed.

I used a pretty liberal amount of grease and it was nothing but a film after one run, and I have limited the amount of suction as well. Im also turning less rpm, and can see where more Rs would cause a bigger concern.

Im going to do a wire drive, I think that will fix the majority of the driveline concerns. I hope so, anyway.