DF41 Motor Recommendations

[leski379]

Hey guys.

Got my DF41 built and on the water. Having a hard time deciding on which motor to try next as my current setup is not working out (big surprise). Currently have a XLX2, std TP4070 2080KV on 6s. 2 minute run times aren't very fun, 430+ amps, stuff gets hot quickly. Already pushed my batteries way harder than I'd like.

I realize the KV is much higher than any of you guys would recommend, but I was hoping it would work for speed passes on 6s, like what I'm used too on my smaller 32-36" boats. (I'm heavily vested in 6s equipment)

I have gotten the DF41 hull just about riding where I want it, but man does it take some power to get this boat moving, and thats what I think I underestimated. I am yet to actually weight that boat as a whole. CG is 29% loaded.

Currently I am logging only about 35k RPM on 6s. Judging by the ose speed calc, this setup should spin faster and I can tell it's never spoolin up like it should causing all the load.

What do you think about a 1700kv 4070? Or since I am mainly just focused on saw passes should I go up a step to the 4070 CM line? Is there a notable difference between the output of the standard TP's vs the CM tp's? Can I run a CM motor for more than a minute on the water without meltdown?

Maybe I really need to suck it up and just go 8s?

Thanks

[screaminyz]

Hey Leski,
Not sure if you got my PM about your bare Velles hull you mentioned in a different post.
Are you still selling it?

[HTVboats]

What propeller? 2000kv really narrows choice of props.
Mic

[leski379]

What propeller? 2000kv really narrows choice of props.
Mic

I've been through my stash. Tried just about everything from a cnc 4519 to a cnc 50mm 1.6 3 blade.

[HTVboats]

With the mass you're trying to move 3 blades are better in my mind but the high KV and revs can't support pitch. 1.9 and 1.6 are going to make heat. 1.4 ratio might be better under 52mm diameter. (ABC 1914/3) While your spending time and money on props an engine change might be prudent. 1400-1600kv will allow more prop area and pitch.
Mic

[leski379]

With the mass you're trying to move 3 blades are better in my mind but the high KV and revs can't support pitch. 1.9 and 1.6 are going to make heat. 1.4 ratio might be better under 52mm diameter. (ABC 1914/3) While your spending time and money on props an engine change might be prudent. 1400-1600kv will allow more prop area and pitch.
Mic

Thanks. Yea I agree I deff need to decrease the KV. This is my largest mono by 10 inches and it's really teaching me a lesson.

[leski379]

Update:

Got a few new props in too try and have made some good progress. Oxi*** *****e makes a cnc 4519 (blue) that I love for my 32-36" boats. Cool temps, all the rpms, great run times. Not a speed prop by any means but quick enough. I am having great luck with a cnc 4819 from OSE. I did everything I can to get my CG to the rear, which gives me about 28.5-29% without adding any weight to the rear (was 30%). Stinger is neutral, trim tabs are mounted UP about 2.5-3.0mm from the bottom of the hull with a slightly more than I like negative angle on the inner tabs. Finally ran the boat on 8s....Now taking donations for more 4s packs.