Delta Force 34 hydro motor

[Tim Cross]

Would a SSS 4082 2000kv motor be appropriate for this boat on 6 s?

[Panchothedog]

Size seems appropriate. I think I would go for a little lower KV if you plan to run 6-s exclusively.

[Tim Cross]

So maybe around 1600? I hear 4s runs decent in these huĺls, but I do hope to run 6s mostly if it's not too much.

[Bande1]

when running mono's you're highly limited on prop size and pitch. The only way to really get real high speeds is higher RPM. The 35k peak RPM "rule" has to be thrown out. What you can do is run the 2000kv then turn down your motor timing and turn down your throttle end points. So you're "over spinning" the drive line then throttling back through your radio and timing. you can then slowly ramp in the power and check temperatures gradually.

That boat is made for P class which is limited to a 3660 motor FYI

[Panchothedog]

Of you have already purchased the motor ( 2000 kv ) I don't think I would set it aside. If you haven't bought it yet, it looks like sss sells a 1650 and leopard sells a 1800. I would choose the 1800 if it were my boat. The closer you get to the ragged edge the harder it is on the ESC, and the smaller selection of props your equipment can handle. From your question, I don't think you intend to race it, just sport running. I am not a fan of the methods
suggested in the above post. Buy the right equipment for your intended use
and it will give you years of enjoyment.

[Bande1]

Of you have already purchased the motor ( 2000 kv ) I don't think I would set it aside. If you haven't bought it yet, it looks like sss sells a 1650 and leopard sells a 1800. I would choose the 1800 if it were my boat. The closer you get to the ragged edge the harder it is on the ESC, and the smaller selection of props your equipment can handle. From your question, I don't think you intend to race it, just sport running. I am not a fan of the methods
suggested in the above post. Buy the right equipment for your intended use
and it will give you years of enjoyment.

there are LOT's of videos on youtube showing 50k RPM boats. Its not uncommon at all.

[Tim Cross]

I do not intend to race this hydro but of course I like to go fast. I haven't purchased the motor yet, but I have everything else hardware wise that was recommended. I thought 2000 kv might be close to edge, so yeah I'll probably do 1650 or 1800. I do appreciate the info for sure.

[Bande1]

2000kv on 6s

[srislash]

Ones driveline HAS to be bang on true to run 50k rpm. This starts with a high end motor collet and smooth transition and bend in flex(if any). Anything short of perfect really doesn’t last long.

Tim, I would go 1700-1800kv for 6s. It should be stable enough to provide plenty of fun. There is lots of tuning once you hit the water to better the speeds

Shawn

[Peter A]

I'm going to chime in here and seriously challenge the high rpm carry on. For someone racing or just sport running, 1400 kv can get you 60 mph+ with a good prop. If zoom zoom, then higher rpm is fine. Lower kv however gives you more resilience against over propping, less chance of burning up gear.
I currently run a 36" ex nitro sport hydro. TP 4060 1350 kv, 6s turning an ABC 1915/17/45. This pushes over 65 mph, and in a race can be a handful in traffic. However it is a solid setup that gives no trouble.
I would recommend the TP 4050 1570 kv motor. I have that in a DF Pirate and that runs around the 55-60 mph for race or play.
Your bigger issues will be keeping that hull on the water over 60 mph.

[Bande1]

I went out yesterday with my 3670 2280kv and ran 6s. motor never went above 93f with a octura x640. Thats about 45k RPM under load with a fully charged battery. motor and esc can easily handle more prop. my old fiberglass hull cannot. nor can it handle a big giant prop as mono hulls will chine walk and torque roll severely. and have trouble cornering. hence why RPM is necessary.

otherwise just run 4s with a 55mm prop....

[Tim Cross]

I really appreciate the info guys, I ordered a TP 4050 1570 KV. I think Peter summed up my situation pretty well. I already knew due to the full length tunnel on this boat that it's gonna trap a ton of air. So as Peter said 60ish and staying on the water will probably be tough. This motor should give me good run time and lots of prop choices. So I'm still at a 4082 size just lower kv than I expected.

[Panchothedog]

Good for you Tim. Nice choice.

[Fluid]

there are LOT's of videos on youtube showing 50k RPM boats. Its not uncommon at all.

Ah yes, the neebie quotes YouTube as a definitive source. Those who have been in the FE hobby for awhile know that just because it?s on YT doesn?t mean it?s a good idea. Just because lots of random boaters do it hardly makes it a good idea. What the YouTubers don?t show you is that their ESC blew up on the next run, their Teflon liner melted or that the motor demagnetized, etc. As mentioned above, to be reliable the setup needs to be spot on and running conditions do too. Over the years I?ve too often seen bad things happen when less experienced boaters try to use high rpm setups, it?s usually a very expensive lesson.

If you want to use YouTube as a guide to build your boat fine, it?s your money. If you want to ask for guidance from the highly experienced FE boaters here on OSE who know the hobby that?s fine too. The OP has made a wise choice with the lower KV motor, although I won lots of races with a 1250 KV motor on 6S so high rpm isn?t always needed. Especially for boaters with limited experience, it is a very good idea to go with a conservative KV. Heck, it may not be a bad idea for some experienced boaters as well.


.

[Bande1]

Ah yes, the neebie quotes YouTube as a definitive source. Those who have been in the FE hobby for awhile know that just because it?s on YT doesn?t mean it?s a good idea. Just because lots of random boaters do it hardly makes it a good idea. What the YouTubers don?t show you is that their ESC blew up on the next run, their Teflon liner melted or that the motor demagnetized, etc. As mentioned above, to be reliable the setup needs to be spot on and running conditions do too. Over the years I?ve too often seen bad things happen when less experienced boaters try to use high rpm setups, it?s usually a very expensive lesson.

If you want to use YouTube as a guide to build your boat fine, it?s your money. If you want to ask for guidance from the highly experienced FE boaters here on OSE who know the hobby that?s fine too. The OP has made a wise choice with the lower KV motor, although I won lots of races with a 1250 KV motor on 6S so high rpm isn?t always needed. Especially for boaters with limited experience, it is a very good idea to go with a conservative KV. Heck, it may not be a bad idea for some experienced boaters as well.


.

do you have proof that its common to have major failures specifically because of RPM? Maybe upload a youtube video proving this? as most motors are conservatively rated at 60k.

things that will cause failure
1. too large of a prop
2. to small of a motor
3. too small of an ESC

increase motor size, decrease prop size, increase ESC, increase cooling. blaming RPM on a failure is silly unless you're spinning flex shafts apart or something.




P.S. I've been casually racing buggies and road coarse since 1997. Thinking that because somebody is new to a mostly dead internet forum means they dont know basic physics is a low effort mentality.