DF Mono Build Tuning Question - Current Draw

[c_michael_72]

I have a new DF 33" mono in the tuning stages. Currently I'm running a Hifei 240, Neu 1527 1.5D on 8s with a X442. The boat has 3 brief runs on it and my main concern is the current draw (spikes). I believe these ESC's can handle surges in the 300+ range but every time I get on the throttle it seems I'm pulling in excess of 240. The boat isn't too wet or heavy IMO and the drive-line is smooth. I've been out of FE for a while now and was just surprised to see this build be such a current hog. Am I overly worried? Any input would be appreciated...Thanks in advance. Below is a screen shot if my third run.

[Fluid]

The motor is the problem - way too high of a Kv for 8S. I run that motor on 8S in my SAW sport hydro and have hit 99 mph through the traps (there is a LOT more there too). That excessive motor Kv forces you to use a small inefficient prop. That hull simply works much better with a 45-50 mm prop.

Options:
- The 1527/1Y motor with a 1250 Kv is much more appropriate and with a more efficient prop just as fast with less risk.
- Run 6S (more reasonable for a boat that size) with your current motor with lower amp draw and similar speeds.
- Run what you have until something gives.


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[c_michael_72]

Thank you sir. Glad to see are still generous, helpful and still in the game. (you helped me many years ago with my first cat build which I will never forget). Anyway, I had two newly rebuilt 1.5d's and opted for one of them over a leo 4092 1730kv, which I may still swap for this build. By the way, I apparently forgot how to use a tape measure as well as this is s 36" DF mono from Steven.

A 6s run, just went great with lower amperage spikes with the existing Neu. Beyond all that, I somewhat understand (theoretically) the PWM rates as well as timing, but for arguments sake, let's say I stick with the Neu 1.5d, on 6 (ish) cells, would I keep the PWM @ 8k and timing @ 16...or does it mean a hill of beans for a sport boat like this?

[Fluid]

That timing (16) is too high for a D wind motor. Set it at low - 0 to 5 degrees advance. That will reduce heat but not compromise speed. The PWM is fine for Neu motors.


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[c_michael_72]

thanks again.

[c_michael_72]

Switching out the Neu for a 2260/8. Switching out the 240 data logger SF for a 300 lite. A lot for this hull, but it's fully reinforced. Any thoughts on props, cell count? 8s, x450ish to start?

[jim82]

IMO I would drop to 6s and start with a m445 prop! Like fluid said 16 degrees is to high for a D wind motor. I use 3.5 but if your only option is 5 that should be fine.

[c_michael_72]

Thanks Jim. Sorry my last post was a bit cryptic. I've pulled out the 1527 in favor of the Lehner. I was reading some of the interesting comparisons on Neu vs. Lehner and decided try one of the 2260/8's I had set aside for a twin build. It's ~1200 kv if I recall.