Rio EP Brushless Setup

[KajunATVer]

Hello, I'm new to the forum and to R/C boats (i have planes, off-road trucks, and helis--all electric). I just installed the following brushless setup in my Rio EP:
Turnigy 36-56 2700kv motor, Turnigy 120A ESC, stock prop, and am powering everything with a Turnigy 5000mah 3s lipo.

On my first run at the pond I first noticed that the cog is off since the boat runs really wet and wants to hook to the left when I stab the throttle. Would moving the cog back help with the hooking? I drilled out the stock coupler to fit the larger diameter motor shaft and made sure all of the set screws were tight, however the flex cable came off but luckily the boat was heading toward the shore and floated close enough to where I could grab it without getting wet:doh:

Any help with my setup would be greatly appreciated, especially since this combo seems to have A LOT of power... maybe too much???

[illz302]

My boat does the same "hooking" even stock. I believe it is because of the torque but I am new to this and I could easily be wrong. I also on my stock rio tried bending the trim tabs up but it didn't really seem to make much adjustment to me.

Could you post some pics and a video? I have been considering converting to BL but I am worried it will be too much for this hull.

[Brushless55]

that little bugger should be fast with that motor!

[KajunATVer]

I don't have any video yet but I'll try to get some when I get the new flex cable and drive dog in. I never had the hooking problem when the boat was stock and it ran beautifully stock after I adjusted the trim tabs some. I added some weight to the stern last night and have the COG approximately 7" from the transom. Hopefully it will run straight now and yes, it seems like it will be crazy fast!

[illz302]

hmm thanks for the info.

[Karfrik]

Kajun,any progress on this lately?.....Al

[KajunATVer]

I actually ran the boat this morning and it's still running way too wet. Under hard acceleration it still wants to hook and torque roll to the right. It actually barrel rolled once but ended up right side up :eek: I adjusted the starboard trim tab and it helped a little with the torque roll. Also, under acceleration the whole boat kind of sinks down and plows through the water. I have my COG at about 30% by adding weight to the stern. I'm thinkin now that the motor is too far forward and I will need to modify the motor mount to get the motor towards the stern more. I'm not sure how I'm going to do this yet since the motor is 44mm on one end and smaller on the end where the shaft comes out (this is the end I have in the mount). If anyone has any suggestions, please let me know.

[KajunATVer]

OK, I moved the motor and mount about an inch toward the stern and removed the weights I added and the boat still runs way too wet. It actually ran better after I removed the weights. It still wants to roll to the right under hard accelleration and seems to be plowing through the water. I'm running the stock prop. Is there another prop I can try that gives more bow lift? I'm now starting to think that the motor is just too heavy???

[Brushless55]

possibly a smaller 3 blade would take alot of the torque roll out
stock prop is 42mm

[KajunATVer]

possibly a smaller 3 blade would take alot of the torque roll out
stock prop is 42mm

Somethimg like this? http://www.offshoreelectrics.com/products.php?cat=Octura+M+Series+3+Blade

[Brushless55]

I think that one is to small
I would try either a 38mm or 40mm 3 blade

[thegreat1]

brushless it is funny that you say the 35 is too small. because that is just the prop i plan on using.

[Brushless55]

brushless it is funny that you say the 35 is too small. because that is just the prop i plan on using.

depends on the setup

[thegreat1]

we are basically running the same thing

[thegreat1]

oh just went back up and saw he is only running 3s that makes a difference. as i am running both 3 and 4s. sorry brushless wasn't trying to start nothing

[Brushless55]

I don't think the 35mm prop will have enough bite on this hull
36mm would be the very smallest I would go, a 38mm could get some great speeds but a 40mm I think would be better

[KajunATVer]

Thanks for the input guys. Where can I find a 38mm and 40mm prop that fits a 1/8" shaft? The 35 was the only 3 blade I found to fit a 1/8 shaft.

[Assocracer]

I actually had to go to a fairly small diameter prop. I'm running the 1440 Octura plastic prop and my torque roll went away, and i get halfway decent speed with a 2s lipo. I'm running a Tekin RS speedo with a Novak 10.5 motor until my 36-56 motor and 60A speedo come.

[Assocracer]

the 10.5 motor is a 4200Kv motor, and the one i have coming is a 2600Kv, but i plan on running 2 2s lips with that.

[Jesse J]

Thanks for the input guys. Where can I find a 38mm and 40mm prop that fits a 1/8" shaft? The 35 was the only 3 blade I found to fit a 1/8 shaft.

you can make a shim out of brass tubing.

have you checked your trim tabs? maybe try taking them off completely and see how she rides.

[Karfrik]

Thanks for the input guys. Where can I find a 38mm and 40mm prop that fits a 1/8" shaft? The 35 was the only 3 blade I found to fit a 1/8 shaft.

Here at OSE,click "Home" up in the links.Thats gonna take you to OSE store.Then look for "tips",click and go there.You`ll find there how to make 3/16" shafts prop fit 1/8" shafts using home made bushings like Jesse is suggesting.Very easy to follow instructions and you save money as its easier and cheaper to get props in 3/16 than 1/8.This way you can use them in bigger and smaller boats!!,...hope this helps,...Al

[goobs]

would this be a good prop?
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXRDF5&P=7

[forescott]

That could be a great prop! I'd like to try one.

[forescott]

you would have to space it down to fit the 1/8 inch shaft.

[goobs]

you would have to space it down to fit the 1/8 inch shaft.

i've got a spacer ready. i think im going to try it.

[forescott]

Let me know how it works out!

[goobs]

Let me know how it works out!

well i ran this in my rio with a cc sidewinder w/ the stock motor on 2s and i think it gained maybe 3mph, it seemed like it was faster anyways. and got rid of some of the torque twist.

also i dont know if its because i cut the scoop out on top of the canopy or because of the prop change but everything was maybe a little warmer than ambient temps outside. and before stuff was getting HOT!

overall i like the prop and would recommend it as an upgrade.
i will get plenty of test time this week since ill be at garner st. park.
after i get back ill try brushless again.