MM with 1717 on 4s???

[millzee]

I'm about to build a MM with a 1717 1580kv motor and my plan is to run 6s so I'll set the boat up for that, I'll be using a t180 esc. My question is, if I have the boat set up for my running 6s and want to teach my son how to drive, can I just lower the rpm by running 4sp2?, will doing this create too many amps? and lastly, am I correct in thinking I'll need more prop at the lower voltage, any size suggestions?:help:

[millzee]

anyone, or will I need a less powerful, higher kv motor to swap in and out for teaching my young fella?

[sailr]

Sounds like a plan. At 1580KV the motor will still put out some reasonable speeds on 4S. It will draw more amps on 4S than 6S so be aware of that and prop accordingly. a 442 prop should be plenty for his learning. You could try a 642 but be aware of the temps!

[millzee]

Sounds like a plan. At 1580KV the motor will still put out some reasonable speeds on 4S. It will draw more amps on 4S than 6S so be aware of that and prop accordingly. a 442 prop should be plenty for his learning. You could try a 642 but be aware of the temps!

Thanks mate, I appreciate you time taken to respond. I'm trying to plan the build b4 the hull arrives so I'll have all the gear needed, If I get away with that set up it'll be a perfect little fun boat for all of us and I can keep some cash.:thumbup:

[Make-a-Wake]

If you use your 6s prop and just run 4s the amps should be less.............speed less as well obviously.

[keithbradley]

Sounds like a plan. At 1580KV the motor will still put out some reasonable speeds on 4S. It will draw more amps on 4S than 6S so be aware of that and prop accordingly. a 442 prop should be plenty for his learning. You could try a 642 but be aware of the temps!

It will draw less current on 4s with the same prop. The faster you turn a prop the greater the load will be (resulting in a higher current draw). That should be a very mild running setup on 4s and great to learn on. If its still too fast you could prop down, or even run on 3s2p. 3s2p would be fairly slow, but I dont know how old your son is or what his current experience level is with RCs.

[Chilli]

My sons old MM was set up with a 10Xl which had 1668 kv. My guess is you would run 40ish to a little better on 4S with a M445 prop. I think a 445 on 3S2P or the 442 on 4S2P would be the ticket for a young boater. The 445 will give you a little less cavitation on start up.

[millzee]

thanks guy's, My oldest son is six, he's pretty good at computer games and he can control my XXL reasonably well so I thought it'll be a good time to get him into the boats. I think I'll bolt a 442 on once it's all ready to go. For me on 6s I think I'll try a m447.

[Steven Vaccaro]

Sounds like a plan. At 1580KV the motor will still put out some reasonable speeds on 4S. It will draw more amps on 4S than 6S so be aware of that and prop accordingly. a 442 prop should be plenty for his learning. You could try a 642 but be aware of the temps!

Jim the only time I can think of, that it would draw more amps is if with the lesser cells the hull was running very wet/inefficiently. I agree with the rest that it will run well.