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ace028
11-13-2007, 12:26 AM
I had a mamba max esc and a 6900 kv motor in my crackerbox, well I am finially going to put something that will actually work for a boat, and was wondering what would be a good choice of a brushless system

Now keep in mind that I have it set up for a 1/8 motor shaft, and I don't really care about it being able to race in a class, I just want it to hall some serious butt, which it did with the previous set up, but that was unreliable.

I will be running 2 and 3 cell lipo and using 1/8 size props and the boat is about 24 1/2 inches long and pretty light, all balsa supports and 1/64 ply skin. I want something that is reliable to run all day without hastle, and if posible has reverse. Thanks.

Rex R
11-13-2007, 02:48 AM
keep in mind that one can use a hex flex coupler with a solid shaft and that the 'short' 5mm to 0.13" is the same length as the 1/8" to 0.13" coupler...my 1st choice/suggestion for a sport set-up would be a feigao 5407L. however if for some reason you don't want to use that then my 2nd suggestion would be the 540 12s. I've got a 7l in my 25" cat and it runs better than 30mph(and I've still got more speed left!) for 1.5 miles w/o getting over 120F
edit
don't try reverse w/ a flex shaft, and use it sparingly with a solid shaft. either a barracuda or a hydra 120 can be set to enable reverse.

ace028
11-13-2007, 10:06 AM
when I do use reverse, I have my reverse speed reduced to 25% of full throttle on the esc, I only use it if I am going too fast to shore so I don't run it on the bank on accident.

Rex R
11-13-2007, 12:19 PM
hope you're using some form of locknut/threadlocker on that prop...

ace028
11-17-2007, 10:52 PM
I was thinking about using the aquacraft brushless set up, but my concern is that its only 45 amp rating. Will it work with a 2 cell lipo with 3800 mah? because my lipo says 77 amps continus discharge rate. or does that mean that it can safely discharge at that rate. and I wanted to use a higher kv motor then the aquacraft one.

ace028
11-21-2007, 10:37 PM
any thoughts anyone? 25" cracker box with supervee power? Would 2 and 3 cell lipo setups = fast and reliable? With high mah lipos like 3800 and up? I don't really care about scale at all here, just a hot rod boat thats fun to drive.

peells
02-03-2008, 02:22 PM
If I were you I would get away from the 1/8" motor size and step up to a 5mm shaft then you will open up a whole world of different motor options because you could then use a flex hex which would reduce down to your smaller flex cable size.
then I would put two 2s packs in series with my hydra 120 running the timing at the lowest setting with about a 1800-2084 kva 540L motor which would help you out for ballast you are too light in the water.