20s Little FOCers on stooge SRB v5#1 comparing to Castle based SRB v5#3

Motors lol

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Yes, do it! I have 6355s up front and 6485s rear. I run half the amps to the front than the rear. Enough to give me a good boost but no front end wheel spin.

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I am so excited that you got thia thing Alex!

I love this thread and i hope you keep it going!

Personally i would love to see how far you can take 2wd first and only after absolutely needing more power go to 4wd :rocket::rocket::rocket::rocket:

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20s won’t overheat if you use reasonable kv motors. 151kv is a great choice on 21s. I haven’t raced my 21s board yet but the motors never even get close to hot.

I’ve also got 20s on 151kv 6355 motors and it never gets above 65 c.

@zero_ads and @poastoast are both running 21s with 205kv and don’t run into too much heat issues

4wd further reduces how hot motors get because it spreads out the resistive losses by lowering amps per motor at low speeds. Or it just lets you push harder lol

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this is where I had been pushing. trying to get the max wattage out of a pair of vescs.
based on specs of the lilfocer that was the reason for 20s. 5x 4s lipos is odd tho.

going 151kv down from 173kv and gearing back up would be an interesting path.

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I likely will stay 2WD and swap the motors out for 151kv or lower before trying 4wd.

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If you are on 173kv you won’t really notice a difference going to 151kv. 20s 173kv will probably work great. I isn’t that what fess has been running?

Also keep in mind, you’re always balancing resistive losses and iron losses. If you go too low in kv, the resistance goes up, so you end up with heat from resistive losses.

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16s gets 205kv hot already…

16s with 205kv runs at a higher max rpm than 21s with 151kv.

You may want to try a lower kv motor if it’s mostly high speed riding that is causing your motors to overheat.

I personally wouldn’t run 21s with 205kv (like Jimmy and Poast). They’re pushing the limits to squeeze out max performance.

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I personally haven’t hit thermal throttling yet, and find this is the best way to get torque and top speed at the same time. Time will tell.

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This is interesting… how much more resistance could really occur by switching to 151 kv? I mean referencing what @fessyfoo said by gearing up again in tandem with 150kv motors… I think may keep those motors in the lower end powerband and away from the high rpm’s which is where iron losses affect the motors the most right?

I have a set of SKP 205 kv motors on my flux diy rn but I was advised not to throw them on my v5 As it would make the motors work harder and overheat quicker? @fessyfoo correct me if I am wrong but I that’s how I understood what you had said.

Why are x5 4s lipos odd? Because of the weight imbalance ? Or is there something more to it ?

I think it will just make iron losses worse.

well 5 is an odd number. :stuck_out_tongue:
but also yeah 3 down one side 2 down the other reminds me i might be ocd a little. it’s probably fine.

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I mean I could add a 6th one but I don’t think there’s really a point unless I ran it in parallel for more runtime?

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correct. not at 20s.

6x4s lipos can do 24s1p 12s2p 8s3p
5x4s lipos can do 20s1p

All settings and gearing kept equal you’d see a 19% decrease in torque, moving from 173kv to 205kv.

As Fess pointed out, you’d also have higher iron losses.

Man, I would just have fun riding the new board. Don’t worry about replacing anything until you kill a motor.

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Just a quick update I had my front truck and rear truck gusset’s reinforced on numbero uno (I had a crash at esk8con and had bent the front gusset) also threw a HD axle on the rear while I was at it :slight_smile: still healing in the meantime

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Big thanks to Moe today for helping me out !!! @MoeStooge

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