|
you wont have any issues at 35-40mph. these are ridiculous scare tactics being discussed here.
|
Quote:
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! |
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. |
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. |
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. |
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.
|
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? |
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. |
Quote:
|
Quote:
|
Quote:
|
Quote:
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. |
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. :) |
This whole discussion is just ridiculous from what I see. I haven't read this whole thread, just pieces of it (as it rather long now), but it really just smacks of CC trying to find something to blame for the early failures of their MMM units. Zippy's being low cost are pretty popular out there and they saw a few failures on the Zippys and bingo. An easy scape goat.
I run many different kinds of packs including zippy 20-30c, zippy flightmax 30c, Neuenergy 30C and 25C, Enerland PQ 25c and 30C, etc... AND I have had many MMM die on me. I prefer not to state the number of replacement that CC has sent me. (Its actually pretty ridiculous.) But now I finally have 3 units that have proven to be reilable. Nothing else has changed in the setups, just the MMM units and these 3 are now lasting. It just ook going through a ton of MMM units that weren't up to snuff to finally find 3 that were. To be fair, I only had one MMM fail violently. and it wasnt when I was running the zippy packs. The rest were all quiet deaths or small poofs of smoke and dead. I seriously think this thread is blown WAY out of proportion. And dont get me wrong. I think CC is a great company and makes some really good stuff. But the early MMM units were not a good example of CC's best work. |
Quote:
I'll take my Zippy powered Savage (that is used for bashing) and run it against a comparable Savage that's running batteries that cost 3 times what mine cost, and my truck will run right with it. I don't have to lower any expectations with my truck...I actually had to detune it to run it! Unless you are gearing to the moon and planning to put one hell of a load on your electrical system, as in top speed challenges or the like, I see no good reason to blow $$$$$$ on highend battery packs. The average basher will be served just fine by running the appropriately sized Zippy packs or some other economical packs. I'm a testament to that. Zippys have gotten a bad wrap and frankly, it's not warranted. Many, many people involved in all aspects of this hobby from land to water to air are running Zippys successfully, and that in and of itself speaks volumes. |
black mamba, that was perfectly said!
|
Quote:
curious, waht battery is the other savage running? because i have the complete opposite results. My NEU outperform my zippy packs any day all day. and dont even get me started on my maxamps.... |
Quote:
|
Quote:
Considering I have my ESC turned down to 30% punch control and my throttle curve is cut way down, the performance I get out of my Zippys is still incredible, and the truck is still bordering on out of control at full throttle. If I were to put the ESC back to default, the truck would be a mess. The good thing about the Flux is that it doesn't discriminate in the least.....it'll flip and do all kinds of circus tricks regardless of what brand packs you are running. lol |
Quote:
|
You know what we need for lipos? Official or at least semi-official groupings. Just like the nimh packs had. Those that were into nimh knew we had entry level sport packs, mid-grade packs, club-level racing packs and uber spendy, matched/zapped, all out competition pro-level packs. Now the lipo companies and industry leaders need to get on board and make it happen. This will help ease the confusion of getting into lipo for the newbies and maybe those not so new to lipo as well.
|
black, you nailed it again.
|
Yeah you always new what you were getting with nimh/nicad matched packs. The 5 year old GP3300 I have here has a label saying cell one is
421 SEC 1.171 AV 16 IR .90 CutOff 5000vCo (whatever that is) 30A DIS 6.0CHG and every cell has a label like that. Who knows what different lipos will actually perform like just from looking at their specs. |
Yea, with NiXX packs you got truly *matched* cells, but I don't think anyone matches Li-X cells, or does any kind of true testing.
|
Any one have new info with running Zippy paks they'd like to inform us about? I'm selling my SMC's as they are to finicky and gonna buy Turnigy or Zippys next spring
|
Mine are still holding strong. My brother in law puffed one pack due to likley overdischarge.
|
For a while I was running my Muggy with stock tires and a 16T pinion (found out later that this was geared for ~90MPH on 6s) and being rather brutal on the throttle and it held up to this for nearly an hour of total use. It held up fine under the Zippies but when I dropped down to a smaller pinion and switched to my Maxamps packs it smoked like a chimney, hmmmm.
|
Quote:
|
Quote:
|
I ran the whole last season on 4s 5000 mAh 30c Turnigy batteries in a converted D8 with the CC 2200kv combo. geared 15/48 and won most races in my class. Even in the hottest days of August the motor never got above 160F after a 15 min. main! I don't need $200.00 battery packs to win races thank you very much:na:
|
i ran a 4s 5000 20c turnigy last season in my mbx5, it was a great battery but its time came. it puffed. but i was great battery while it lasted. strong lil pack
|
Quote:
|
are zippy lipo's safe to use with MMM?
http://www.rc-monster.com/forum/showthread.php?t=24618 set-ups used in the mud are zippies, everyone at club runs zippies (oh...but i run zippy and turnigy). answer... YES!!! |
Cool, i'll be purchasing some Zippy or Turnigys next spring then, i'm done with SMC
|
So what was the final resolution on this? Do cheap lipos cause ESC failures or not? If so could somebody please explain the technical reason for this. I'm just a Mechanical Engineer Dummy, so 'splain it slowly. All I saw in these posts was something about voltage ripple, didn't make sense to me. I don't understand how a DC power source would "amplify" a voltage ripple, cheap or otherwise.
Thanks |
the conclusion:
hobbycity lipos are fine for the MMM as long as you get one with enough of an amp rating for your rig. if you are running a buggy, a 100a constant rating or higher is recommended. if running a truggy or not so heavy MT, 125a or higher is recommended. if running IE, an extended savage flux with 7" tires that weighs 15lbs, 150a or higher is recommended. all these ratings are for rigs geared for less than 50mph. for over 50mph, but less than 65mph, add 25-50a. for over 65mph, unless you are just doing a few speed runs, all i have to say is good luck:drunk: maxamps packs are more likely to cause problems than the zippy and turnigy packs. so, as long as you get a high enough rated battery, you should be fine. edit: some people may be able to get away with smaller or lower rated packs. it all depends on their driving style. if you are just going to bash, you might not need huge c ratings, but if you are going to drive in tall grass, sand, gravel hills, or race it, you will need better packs. |
Quote:
The problem is the MMM esc has such a low internal resistance, it is more vulnerable to any changes in amperage and voltage outside of it's normal operating range. This is why Castle say you MUST use high quality cells that can control and absorb the voltage created during regenerative braking. Rather than lumping it back through the ESC. Hope this helps:intello: |
update-My Flux and the original ESC are still working just fine exclusively on Zippy packs. I have since moved to Hobby City's Flightmax series of packs as the Zippy H packs I was using have been phased out. Either way, I still run the old packs and have had no problems to note other than a wire coming off of one of the Deans on the ESC side.
The basis of this argument of whether or not Zippy packs and ESC failure go hand in hand holds no water per se as there's a whole lot of guys/gals running Zippy or Hobby City lipos in their MMM powered rides and they are not having issues. Consider this the RC version of Myth Busters. Busted. lol |
| All times are GMT -4. The time now is 04:41 PM. |
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.