Are Zippy Lipos safe with a Castle MMM Speedy?

you wont have any issues at 35-40mph. these are ridiculous scare tactics being discussed here.

[fastbaja5b]

Originally Posted by Chadworkz

Wow, I must say, I am now thoroughly confused and scared to death...heh!

A few details;
I have a nitro 3.3 Revo that I converted to brushless using Mike's RCM motor-mount and custom carbon-fiber Battery/ESC/RX trays that I made. It has the V3 MMM/2200kV combo running through the nitro transmission with a forward-only conversion, Pro-Line Bow-Tie MTRs on Pro-Line 23mm ½" off-set Velocities, a ton of carbon-fiber, titanium, & other lighter-than-stock parts throughout...and I am also planning on running the brakes & reverse via the motor.

I was planning on running a pair of Zippy Flightmaxx 4S 2650mAh packs in parallel for 14.8v @ 5300mAh, but am now questioning that choice after reading this thread, but wanted to ask a few questions before I make my final decision.

I am not a speed-freak, and I am not going to race, I just want a quick truck that is reliable enough to bash around the yard, in the chert-pit, and do jump-tricks off of my ramp...maybe 35-40mph max. Right now, besides the batteries, my biggest question is gearing, and about the transmission...

...is the overall gear-ratio of the nitro Revo transmission any different than the E-Revo transmission? If so, what spur and pinion would you guys suggest for my setup and what I want out of the truck, as well as if the ratios are the same for both transmissions? Like I said, I don't want all-out speed, just 35-40mph and reliability enough to do what I said above. As for the batteries I chose, I believe they will work just fine for my needs, but I really want to make sure before I damage something, and I would really appreciate help from you guys since you really know your stuff.

Thank you so very much for any help you guys can provide, it will be much appreciated!

P.S: I am going to run a set of Mike's V3 1/8 Revo Hybrid Diffs (buggy ratio) in the future, so I may need some help selecting a spur/pinion for that setup as well...

No matter what you do someone somewhere will say it's wrong. I have run a converted Revo with a MMM speedy and a Medusa 36-60-2000 motor and it was fine that was running Reedy 5000mah 20C Lipos (2 * 2s packs)

so your set up should be ok from what I can see.

I think on 5/6s it's more critical than on 4s unless you gear down severely but then of course you risk an undergeared motor so either way ur stuffed lol!

My converted Revo, 4s Lipo stock spur and 14t pinion with the 2000mah was a handful but it was super reliable (now in the hands of a mate who is known to be a magnet for breaking things, but he hasn't yet!), yours should be even quicker, although with the extra torque of the MMM motor, I'd explore putting in the Robinson Racing metal gears inside the transmission!

Good luck with the project!

[Finnster]

Personally I think the whole thing is a bit of CYA from castle, and I would only really be concerned about it if I was pushing my system to the limit. What you are doing will not, and that just fine.

My first revo conversions used a MM on 4 and 5S and ran 10C batteries. they had no problems, but I didn't abuse them either. Decent batts and setup and it will be fine.

As far as gearing goes, use this calc of BrianG's IDK all the ratios, but its quite easy to just use the drop downs to get what you want. FWIW, I used 3.5v/cell and 6.7" sized tires to get the speeds I was seeing on my radar gun using maxx mashers. YMMV, but it gets you close. Aim for 40 and a ~32K rpm motor and you will be golden.

[Finnster]

What C rating are the batts btw? It should be at least 20 with that capacity. You want to be able to supply ~100A continuous. Else get bigger batts.
the 10C batts I had back in the day were 8000 mah, and were really more like 15C batts. That still 120A cont.

[Chadworkz]

They are 30C/50C batteries...and thank you guys for the replies, I really appreciate it!

Edit: Different vehicle, but what pitch is a 1/8 center-diff spur? I am almost positive it is an Ofna 55t spur, but I think all 1/8 spurs are the same? Anyway, I believe it is Mod-1, I just want to make sure...thanks.

[emaxxnitro]

so neu 30c 5000's should be great cells for the mmm right. all i have fed my mmm up till now is maxamps and zippy.

[Sammus]

neu cells are about a billion times better than maxamps, and probably nearly twice as good as zippy, so you should be right to go :p

but in all seriousness, wtf? a couple of idiots trying to set the land speed record on cheap dodgy batteries break there car and suddenly theres 17 pages of fear that you cant run the mmm with anything less than the aboslute pinnacle of battery tech. geez chill out guys, I often run 2300mah A123 cells in 7s and haven't had a problem with it. ANY 4000mah 6s lipos are going to be better suited than that. just dont do anything stupid. and emaxxnitro: that means if you really do want the worlds second fastest erevo, yes you will need good cells.

and btw, what is a mamba monster pro?

[Sammus]

Yeah, I'm pretty certain the Neus are enerlands. Not 100% though.

This thread is interesting for sure. With that said, I run Zippy lipos in my Savage Flux. I run the soft case 3S 3500 30C constant/40C burst and the soft case 3S 5000 30C constant/40C burst packs. 0 problems and I've run them in this truck since early February. The truck uses the stock 20/44 gearing, runs 6.5-7" tall tires and is tuned with Castlelink, specifically the throttle punch and throttle curve. The auto lipo cutoff is set to 3.5v per cell. Firmware is 1.21. The performance of the truck, even when neutered with Castlelink, is superb. The batteries never get hot and the ESC never gets hot-the fan kicks on and does its job like it should. From my experience, I'd be hard pressed to not tell somebody to use Zippy packs.

I will add that Castle really has nothing to gripe about because HPI and Traxxas both state in their user manuals that you can run anything from a 6 cell nimh stick pack up to a 25C 3S lipo with the Mamba Monster. Certain Zippys meet that requirement, and the ones I run do meet it. If Castle has a problem with us running Zippys, they need to sit down with HPI and Traxxas and get things sorted out with the battery pack particulars. And they need to let the end user know, in writing, what should be used and what shouldn't. From my perspective, it appears Castle is not on the same page as HPI and Traxxas, or vice versa. And this is a major issue considering the amount of Savage Fluxes and BL E Revos that have been, and will be sold. Not to mention all the "loose" Mamba Monsters that have been sold and installed in other kits or conversions.

Originally Posted by Jeremy1976

Great metaphor!

Would be BUT, there are a couple of Chevy products that will run with a Ferrari. The Z06 Corvette and the ZR1 Corvette. There's always a fly that will land in the ointment.

Originally Posted by RC-Monster Mike

I will put the performance of my packs against any other out there. The recent failure that happened to be using my packs is of a different type than described in this thread - the gearing was low enough for even the lower end packs when the failure occurred and seems to be unrelated to the batteries - I am not going to speak for Castle or anyone else on the particulars, but i can say with certainty that my batteries are NOT a problem, as I did pretty extensive testing (almost a year) before offering the packs for sale. :)

So wait, you've tested ALL the batteries you sell on your site to be gaurenteed to power a Flux without killing it?

[JThiessen]

Originally Posted by Freezebyte

So wait, you've tested ALL the batteries you sell on your site to be gaurenteed to power a Flux without killing it?

No, he is referring to the packs he makes.

[RC-Monster Mike]

Originally Posted by Freezebyte

So wait, you've tested ALL the batteries you sell on your site to be gaurenteed to power a Flux without killing it?

Well lets not put words in my mouth here - there are far too many variables - if you used a 4s 2600mah pack in the Flux geared for 50mph, I would expect problems. The packs we sell are top quality, but the customer still has the responsibility to select the proper "tools for the job". A properly selected pack and proper gearing with any of the packs we sell will minimize the possibility of failure - specifically battery related failure. Nothing has 100% reliability, and there are many factors that can cause failure - the key is to minimize the potential causes in order to maximize the reliability - this same thought can be applied to anything you do and is the real message here.
Zippy or Flightmaxx in and of themselves are not a "cause of failure" most likely - its the combination of a lower end battery and unrealistic expectations leading to unrealistic operating conditions.
If you run a Ferrri on low grade gasoline, you have nobody to blame but yourself when it develops a ping and runs like crap. If you can't afford "premium", then get a Ford. The same message applies here - if you run lower grade batteries, you must lower your performance expectations and make the appropriate gearing and setup considerations to ensure longevity. :)

I agree with a lot of what mike says but at the heart of the issue is that people who are making an assumption about a particular battery without seeing any real discharge data or long term performance data based what appears to be on the cost of the battery. ie low cost HAS to be an inferior product. sometimes it is and sometimes its not.
id like to see a discharge curve on a 3S 30C FLIGHTMAX VS a neu vs one of mikes batteries( i just ordered one myself). To this point i have pushed my brushless erevo and emaxx very hard with tall gearing with 6S 20-30C zippy lipos and have had no issues.
i have not had any failures with the neus, i have had failures with older Maxamps but not their new 35c packs. I think these are very very good packs but at the wrong price point.

[RC-Monster Mike]

As a general rule, you get what you pay for. There are of course exceptions to every rule. Hobby City freely admits that their Zippy and Flightmax packs are lower end packs - expect less cycles and lower charge rates vs. the higher cost packs(there is a quote on the boards here somewhere). They are a good "value", but the expectation that they are the same quality and performance as a higher end pack costing 2x as much is unrealistic. This doesn't mean they won't work or are "bad", but we have to be realistic. Likewise, your idea of "pushing your erevo and emaxx brushless very hard" may differ from someone else's idea of the same, which is part of the danger of the internet - no 2 people operate in exactly the same conditions, so a lot of info requires speculation.
I also agree on the newer Maxamps packs - very good packs - pricey perhaps, but far better than their previous generation. :)