Good target RPM?

[FighterCat57]

I'm curious about the target RPM for a brushless setup.

What is too high? What is too low? What is just right?

How do I know?

Right now I'm targeting 29 - 32k Peak RPM by V x Kv method.
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HERBAL VAPORIZERS

[FighterCat57]

I guess this is a really silly question, or just too vague?
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Chevrolet big-block engine specifications

[Jeff Wohlt]

Those are good rpm levels as long as you do not over prop. I like 27-30,000. Also depends on the motor...some can keep it up while others can't.

[FighterCat57]

Those are good rpm levels as long as you do not over prop. I like 27-30,000. Also depends on the motor...some can keep it up while others can't.

Is that actual or theoretical peak?
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30 Rock Advice

[Jeff Wohlt]

Based on non-loaded rpm so you will be down to 24,000 or so.

[FighterCat57]

Based on non-loaded rpm so you will be down to 24,000 or so.

Nice.

I've heard of a few running 4s 2700Kv without any problems, which is nearly 40k RPM.

What is the main reason 40k is too high and 32k is not?
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WEATHER EYE

[Jeff Wohlt]

Well a good balanced motor can do that but the cheapos out there will throw parts, bearings or something. You can do it for a while but it will go.

Now a NEU or Castle can probably handle it but they have more thorque than rpm in most cases.

[FighterCat57]

Well a good balanced motor can do that but the cheapos out there will throw parts, bearings or something. You can do it for a while but it will go.

Now a NEU or Castle can probably handle it but they have more thorque than rpm in most cases.

Oh, so it's about shaft balance and the bearing system. That makes perfect sense. Really, I think spinning a dremel shaft at 30 KRPM is kinda surprising!

Thanks for taking the time to clarify this, it's a bit confusing putting all of this together, I'm still wet behind the ears when it comes to building and calculating.
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Vaporgenie reviews

[Brushless55]

it also depends if your sport boating or going after a SAW record
take the SV27 has an unload rpm of about 27,000rpm
and the UL-1 is about 30,000rpm
and some SAW runs are 40,000rpm +

[Simon.O.]

I am a solo boater and the pond I run mostly in is good for staight runs, I run anywhere up from high 20kprm to high 30krpm.

It is safe to say that some of my setups are close to SAW type.

I like small props and wicked rpms, it just sounds nice!

[FighterCat57]

This really clears up the RPM range thing. I'll stay away from over 30k with anything that I don't feel is completely balanced and of good quality bearing/drive setup and shoot for 26k with cheap stuff. =)
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New Jersey Dispensaries