Are Zippy Lipos safe with a Castle MMM Speedy?

[shaunjohnson]

if only there was a way to get this important info out to the newbies out there...
i mean...WHO in their right mind would use 18 cell nimh batts????
there need to be gearing guidelines, maby a gearing chart?
in the castle manual or castle link CD a link to brian G's gearing calculator?

BUT after hearing the above castle rep stating that the return rate is very low...that makes me very happy :D

[fastbaja5b]

Wow I let a cat out here didn't I?

The main reason I initially asked is that when I bought my Flux (my 32nd RC to be blunt, and only one I still have now) I thought I had a bit of knowledge on me, 2 MMM's down, 4 MM's, a Brushless E-Savage that I had running uber sweet, and then this manual tells me to GEAR UP for 6s? The Manual even states 4s - use 20t pinion, 6s - use 25t pinion, I mean WTF?

I know my 5000mah 30C 2s Lipos haul the truck around happily on 4s with the 20t pinion (on a 100 degree day the packs come off after 20-25 minutes at 130 max), my intention was to run 6s with say an 18t pinion, which is contrary to the manual, and locally the HPI distributor in Australia has been implying that if you run anything "other" than the 25t pinion on 6s you may be out of warranty? This all stemmed from someone running Maxcramp packs on a 6s set up with a 20t pinion and blowing the ESC.

So my query was, could I, on stock gearing (20/44) run a 6s Lipo set up - Dual Zippy H 5000mah 3s 20-30C and be "reasonably within spec"

I know if I gear down to 18t I'd pull less amps, but I was concerned that the HPI Australia distributor and the Manual were telling me to run 25t

so I wondered, had I missed something?

As it stands now? I do wish to try a 6s set up, but am thinking 18/47 is a better starting point and really watch my temps.

Is this reasonable or do I need my head examined?

...my last RC was a Baja, so it's possible all that two stroke got to me!

[JThiessen]

Originally Posted by fastbaja5b

As it stands now? I do wish to try a 6s set up, but am thinking 18/47 is a better starting point and really watch my temps.

Is this reasonable or do I need my head examined?

...my last RC was a Baja, so it's possible all that two stroke got to me!

Just my .02...you have been asking and re-asking this same question on multiple forums. I have read where you have recieved an answer, but you dont seem to want to hear it. I'm not trying to insult you, but it's apparent that if you want to operate within warrantable parameters, HPI's stance is you run 6S on 25T (and it appears that Castle is backing that same claim). Its either that, or run it how you want, and take your own warranty out (your wallet), which is how most of us have ran our stuff for many years.
I too have run mine with the 6S/20T, and I liked how it ran - but it was a bit on the uncontrollable side. I'd like to take some of the pep out of it - and the 25T may just do that (as opposed to 4S, which just seemed too tame for me). However, that is going to make it a PIA to run both 4S and 6S in one outing. So I need to rethink and make a commitment to one pack set up - which kinda sucks IMHO.

[skellyo]

Originally Posted by JThiessen

I too have run mine with the 6S/20T, and I liked how it ran - but it was a bit on the uncontrollable side. I'd like to take some of the pep out of it - and the 25T may just do that (as opposed to 4S, which just seemed too tame for me). However, that is going to make it a PIA to run both 4S and 6S in one outing. So I need to rethink and make a commitment to one pack set up - which kinda sucks IMHO.

If you want to take the pep out of it, either gear way down or drop your voltage down from 6S. Putting the 25T pinion on it is like trying to slow down a drag racer by putting monster truck tires on it...it's just not an intelligent solution to the problem. All you'll do is increase the current draw and start potentially causing heat issues.

The whole point behind what the guys from Castle are saying is to use common sense when gearing these trucks regardless of what the manual says. This post backs that up:
http://www.rc-monster.com/forum/show...&postcount=111

[lincpimp]

Originally Posted by skellyo

If you want to take the pep out of it, either gear way down or drop your voltage down from 6S. Putting the 25T pinion on it is like trying to slow down a drag racer by putting monster truck tires on it...it's just not an intelligent solution to the problem. All you'll do is increase the current draw and start potentially causing heat issues.

The whole point behind what the guys from Castle are saying is to use common sense when gearing these trucks regardless of what the manual says. This post backs that up:
http://www.rc-monster.com/forum/show...&postcount=111

I think by pep he meant the large quantity of torque. Gearing up will put more load on the motor, and may cause it to spool up a bit slower, but it is not a good idea. Maybe adding some more punch control, or some expo to the throttle channel... I guess the CC motor is just too powerful for him

[skellyo]

Originally Posted by lincpimp

I think by pep he meant the large quantity of torque. Gearing up will put more load on the motor, and may cause it to spool up a bit slower, but it is not a good idea. Maybe adding some more punch control, or some expo to the throttle channel... I guess the CC motor is just too powerful for him

I figured that's what he meant, but it's still not a good idea. Reducing the voltage to the system is a much better alternative to resolve the issue. With 6S, it's possible that the 25T on the stock tires may very well cause heat issues with the MMM. That puts it geared for 70mph without accounting for any tire ballooning.

[JThiessen]

Originally Posted by lincpimp

I guess the CC motor is just too powerful for him

damn----yer killing me!!!! But, I must humbly say, that yes, it is...

Yes, my little issue is one of control as related to keeping the front tires down a little more. Yes, adjusting the punch control, and maybe playing with the EPA on my DX3 might help some too. Going to the 25T pinion should help with that some. Yes, load(s) on the motor will increase, but that is not necessarily a bad thing (insert all previously mentioned signs of a toasted motor). Until I experiment with it, I have no reason to fear it, correct?

Has anyone heard if Traxxas has any similar recommendations with the ERBL? They may not since they dont carry the warranty.

[fastbaja5b]

Originally Posted by JThiessen

Just my .02...you have been asking and re-asking this same question on multiple forums. I have read where you have recieved an answer, but you dont seem to want to hear it. I'm not trying to insult you, but it's apparent that if you want to operate within warrantable parameters, HPI's stance is you run 6S on 25T (and it appears that Castle is backing that same claim). Its either that, or run it how you want, and take your own warranty out (your wallet), which is how most of us have ran our stuff for many years.
I too have run mine with the 6S/20T, and I liked how it ran - but it was a bit on the uncontrollable side. I'd like to take some of the pep out of it - and the 25T may just do that (as opposed to 4S, which just seemed too tame for me). However, that is going to make it a PIA to run both 4S and 6S in one outing. So I need to rethink and make a commitment to one pack set up - which kinda sucks IMHO.

Got it, so what you are saying and what you are saying Castle is saying is to gear 6s by the manual which is a 25t pinion and forget ALL conventional wisdom on the matter.

...if you say so then thats what I will do........

I don't want to lose my warranty.

[Pdelcast]

Originally Posted by fastbaja5b

Got it, so what you are saying and what you are saying Castle is saying is to gear 6s by the manual which is a 25t pinion and forget ALL conventional wisdom on the matter.

...if you say so then thats what I will do........

I don't want to lose my warranty.

That's certainly not what I said.


I suggested you use the smallest pinion that gives you the performance you want and isn't too hard on the batteries/motor/ESC. You can test this by checking temps during your runs.

If you see temps above what is safe (120F or so), back down on the pinion.

Smaller pinion means less load on the motor, and cooler temps, and longer life.

[e-mike]

also the air flow in the body and the timing setting to lowest

[JThiessen]

Originally Posted by Pdelcast

That's certainly not what I said.


I suggested you use the smallest pinion that gives you the performance you want and isn't too hard on the batteries/motor/ESC. You can test this by checking temps during your runs.

If you see temps above what is safe (120F or so), back down on the pinion.

Smaller pinion means less load on the motor, and cooler temps, and longer life.

Yes - this is exactly what Castle can and should say. They can't contradict HPI on here, nor should they.

FWIW, I stubbornly wanted to try 6S/25T on the Flux tonight, and after 20 mintues, I decided it wasn't worth the hassel at this point. It earned my first failing grade for it with the work required to change the pinion. Its definitely NOT a quick change situation. So if you have one, better figure out what batteries you are going to run, gear appropriatly for that, and go have fun - dont bother with different sizes of batteries assuming you'll just quickly change the pinion. There's more on that in my Flux thread in the HPI section.

...my last RC was a Baja, so it's possible all that two stroke got to me!

I'm debating on whether my "next" rc should be the baja.

If I do... I'll make sure to read the

[fastbaja5b]

mate get the 5T, it's on my list once I move to an area more suited to running them.

The manual on the Baja's isn't too bad actually.

and they're a s#it load of fun!

[Finnster]

Yeah, the only time I would consider going up in the gear is by also going to much smaller tires and using for speed runs on street only. With the lighter tires and lower rollout, the motor load may actually drop. No way to know w/o testing, but I'd start with the lighter tires and smaller gearing and work my way up from there.

[superek4]

I m so sick of mmmv3 failing me I sold it off n trying hobbywing 150a ezrun with program card d specs looks good n price is even better