head of the river cat with medusa motor

[DINO7]

hello to fe maniacs.the chinese agitator is my first serious fe boat.i bought it like new from Disar.so i installed my medusa 36-50-2200V2 that i had before in my full modified e-savage.the boat is excellent for first fe.im very happy with the only 50mm long medusa in it.i have done some measurment today with my watts meter to find out exactly what happens.so here they are.its with 3S and 4S set-up and with K40-K42-K45 graupner props.batteries are zippy 2200 3S 25C in parallel and rhino 2350 4S 25C in parallel to.

3S-11.1V

K40 prop
max amps=60
watts=678
speed=40km/h

K42 prop
max amps=64
watts=707
speed=49km/h


K45 prop
max amps=80
watts=852
speed=52km/h
with bigger k45 the motor temp was 35C and ESC was 27C

4S-14.8V

K40 prop
max amps=90
watts=1292
speed=50km/h

K42 prop
max amps=97
watts=1357
speed=60km/h

K45 prop
max amps=117
watts=1601
speed=65km/h

the temp with K45 was at motor 53C and ESC 43C.
what do you think FE specialist?
sorry for my english.

[bustitup]

I'm a true believer in Medusa but I will say I think you are pushing your luck with a 50mm motor in that hull and especially in an e-savage......how much time do you have on that motor in the savage?

[ED66677]

if we're talking about the 32" cat, a 36-50 motor might be a bit too small, I would use a longer can motor with a lower KV under 6S, I know the medusa is probably better than a Feigao XL (36-74), but you're pulling 1600 watt (burst I guess) and only takes her at 65km/H...

[DINO7]

im thinking about 36-60-2200V2 .the 36-50 medusa had it on e-savage about 5 months.this 50mm motor is far better than my 60mm feigao 9L.i will try some 1.6 pitch props and will see what top speed will be.

[calcagno45]

I would look into atleast the 70mm Medusa if you want to stick with Medusa. a 2000KV should be perfect on 4s.

I would stick with those props, unless you are going to run a 637, maybe 640...

[DISAR]

Dino7 moved from brushless cars to brushless boats with great enthousiasm. Within 2 months remarkable progress and likes testing a lot. The boat runs very nice with the medusa and above 65 km/hr becomes unstable (read to fly) maybe needs extra weight. The 3670 with extra weight on the bow may make it better. By the way he runs the boat with an ESC "ELF" 100A (e-bay) which is top. Rated for 100A but pulled 117!
Thanks for sharing your records.

[lomdel]

...Thanks for sharing your records.

I wish we all could share our stats in this guy's format Very informative at a glance...
Your boat can reach much higher speeds, dude! Invest in longer motor. Just check the kv rating that rpms stay reasonable with the lipos you got.

[ozzie-crawl]

here is some of my findings with these hulls and fiego motors.7xl 4s x440 prop detounged 79amps 55mph. in this hull a 8xl on 4s and depending on prop will give you good run times and do around 45-50mph

[bustitup]

im thinking about 36-60-2200V2

for a few dollars more go with the 70mm medusa

[DINO7]

what rpm is ideal for this hull?

[Flying Scotsman]

The rpm is not the answer it is power, motor and prop and are you trying to run a sport or SAW setup. FE boating is a challenge What type of hull are you running and length, as I am not familiar with an agitator? If it is 32" cat, the batteries will have to changed for more mah, are they 1P or 2P

Douggie