Arrma felony

[JJ23]

I hav a arrma felony changing it to spektrum 8s 1250kv motor Whats the best gears to use for speed runs & bashing

 

[Greywolf74]

For speed runs a 1250kv motor isnt the way to go unless you can run pinions the size of spur gears. Personally Id look at a Castle 2200kv on 6S for speed runs. As for gearing your gonna want to get as close to 1:1 gear ratio as possible or even less than 1:1 if you can and have the torque to spin it. Thats the only place where your 8S 1250kv is going to be faster than the 2200 on 6S but I'm pretty sure you wont be able to get less than a 1:1 ratio.

 

[JJ23]

For speed runs a 1250kv motor

For speed runs a 1250kv motor isnt the way to go unless you can run pinions the size of spur gears. Personally Id look at a Castle 2200kv on 6S for speed runs. As for gearing your gonna want to get as close to 1:1 gear ratio as possible or even less than 1:1 if you can and have the torque to spin it. Thats the only place where your 8S 1250kv is going to be faster than the 2200 on 6S but I'm pretty sure you wont be able to get less than a 1:1 ratio.

isnt the way to go unless you can run pinions the size of spur gears. Personally Id look at a Castle 2200kv on 6S for speed runs. As for gearing your gonna want to get as close to 1:1 gear ratio as possible or even less than 1:1 if you can and have the torque to spin it. Thats the only place where your 8S 1250kv is going to be faster than the 2200 on 6S but I'm pretty sure you wont be able to get less than a 1:1 ratio.

I have 8s spektrum 8 I'm running with it

 

[JJ23]

I have the spektrum 160 esc 8s

 

[Greywolf74]

the issue isnt with the ESC. The issue is that a 1250kv motor on 8s is only capable of about 37,000rpm. The 2200kv on 6s is capable of almost 49,000rpm. So unless you can run something a lot bigger than a 34T mod1 pinion gear the 2200kv from Castle Creations is going to be faster than the 1250kv. You can use that ESC with the 2200kv motor though

 

[tntpoof]

id try to achive the max rpms the esc can handle..I'm pushing a few of my http://poseidonrc.com/index.html a few thousands past there rated max rpm .I'm only running 4 cells .

 

[HPIguy]

id try to achive the max rpms the esc can handle..I'm pushing a few of my http://poseidonrc.com/index.html a few thousands past there rated max rpm .I'm only running 4 cells .

The ESC has nothing to do with RPM, only amp draw. The ESC will only hand out what the motor asks for amp wise, even if it's more than the ESC is rated for and fries the ESC.

 

[tntpoof]

esc has a major amount on rpms . if esc has a 50k limit you aint going past that

 

[Greywolf74]

Once again the ESC has NOTHING to do with RPMs. Only 2 things that affect RPMs is how big of a lipo you're using and the kv rating of the motor

 

[tntpoof]

I see some just post and dont know the limits of speed controls.. and no sensor wire needed .LOL

 

[Cwimp84]

Man google must be a hidden thing these days. Esc’s with rpm limits , interesting lol. But greywolf hit it, I've ran 1250kv on a felony on 8s and its pointless. I can get the same speed out of a 2050kv on 6s. My sweetspot is 1650kv castle Motor and infraction has leopard 1680kv. I run one on 8s one on 6s. Perfect

 

[Jayday33]

the issue isnt with the ESC. The issue is that a 1250kv motor on 8s is only capable of about 37,000rpm. The 2200kv on 6s is capable of almost 49,000rpm. So unless you can run something a lot bigger than a 34T mod1 pinion gear the 2200kv from Castle Creations is going to be faster than the 1250kv. You can use that ESC with the 2200kv motor though

My 8S 1250kv spectrum system with a 34tooth pinion is way faster than that 2200kv castle on 6s. Not even close! With it at 70% so you saying you need something bigger than a 34 is incorrect. I could actually run a 28-30tooth and smoke that castle system

 

[Jerold]

Stating the obvious here, but lower KV means more torque, but you need more volts to get the same top speed. I use 8S for speed runs, but if I was bashing I'd probably go with 6S just because of expense and it's not sustained speed (RPM).

Whatever setup you choose you may need to adjust the gearing. Again, stating the obvious, lower gears means more acceleration, or tire spin in most cases. Higher gears will give you more top speed, but you need some room for that. The key is to make sure you are not over heating the motor/ESC. So I would start sort of small, run it and check the temps. You don't need a heat gun, just your calibrate finger. If you can leave it on there the temp is OK. If not reduce the gearing.

For reference when I say lower gears, I mean smaller pinion and/or larger spur.

 

[Greywolf74]

My 8S 1250kv spectrum system with a 34tooth pinion is way faster than that 2200kv castle on 6s. Not even close! With it at 70% so you saying you need something bigger than a 34 is incorrect. I could actually run a 28-30tooth and smoke that castle system

My point was that unless you can overcome the RPM difference with gearing, then the 6S is going to be faster. a Castle 1515 can spin a 34T spur on a Felony for speed runs so unless you can get a bigger spur than that on the Spektrum 1250kv then the 1515 is going to be faster. Its a rather simple concept.

 

[Grizz03]

ESC's do have limits. They can only turn on and off the coils so fast.

Simple google search

 

[Greywolf74]

ESC's do have limits. They can only turn on and off the coils so fast.

Simple google search
View attachment 177625

Yes, but no one talks about that because as long as you are running within the specified voltage ranges you aren't hitting that hardware limitation, so it's a moot point. That's why manufacturers don't list it as a spec, or at least not most of the main brands anyway. Just because an ESC has limits doesn't mean it has anything to do with dictating what RPMs the motor run at.

This point wasn't even central to the OPs topic, so I can only surmise you're trying to pick yet another fight with me 2.5 years after this post was even posted.

 

[Grizz03]

.This point wasn't even central to the OPs topic, so I can only surmise you're trying to pick yet another fight with me 2.5 years after this post was even posted.

Get over yourself! My reply was to this comment:

Man google must be a hidden thing these days. Esc’s with rpm limits , interesting lol.

But since you brought it up do you still stand by this comment without trying to justify it's a moot point?

Once again the ESC has NOTHING to do with RPMs. Only 2 things that affect RPMs is how big of a lipo you're using and the kv rating of the motor

Which was clearly to contradict:

esc has a major amount on rpms . if esc has a 50k limit you aint going past that

Yes, but no one talks about that because as long as you are running within the specified voltage ranges you aren't hitting that hardware limitation, so it's a moot point. That's why manufacturers don't list it as a spec, or at least not most of the main brands anyway. Just because an ESC has limits doesn't mean it has anything to do with dictating what RPMs the motor run at.

What does this have to do with my comment? I never commented or disagreed with that.
Only commented that there is a max RPM limit an ESC can support. I dealt with Sevcon and Curtis controllers.

 

[Greywolf74]

Get over yourself! My reply was to this comment:





But since you brought it up do you still stand by this comment without trying to justify it's a moot point?

Which was clearly to contradict:







What does this have to do with my comment? I never commented or disagreed with that.
Only commented that there is a max RPM limit an ESC can support. I dealt with Sevcon and Curtis controllers.

You're the one that needs to get over me. All you're doing is following me around the forum trying to argue with me. You're pathetic.