Krawlin

Wild is right. Batteries are efficient in how well they can hold up to a given amp draw. NiMH are good for about 45 amps, and at that rate they heat up fast, which is wasting energy. LiPo's can handle massive amp draw without even getting warm, thus do not waste energy on producing heat, thus more efficient. Same goes for motors. An efficient motor uses energy in rotating its shaft rather than wasting it on producing heat. An inefficient motor wastes energy on producing heat rather than turning the shaft. That is why high Kv motors are inefficient, because with any significant load they get hot and waste energy from the battery on producing heat.

klaze

Hahhah.


Are you a mod? What's with this forum and people pretending to be mods?

patatchim

There this thing, that its called internal resistance. It affects all batteries, some more others less. Thats why you don´t see a linear graph on discharge charts for batteries.

Lipo is a lot more efficient than nimh, the current that you put is the current that you get, this is current/discharge efficiency.

Also: Lipo have a small internal resistance compared to nimh. This is why lipo maintains their tension pretty well when a load is placed. This is why lipo is more efficient than nimh.


So, yes, efficiency is the correct term.


If you want to know more, here are some terms that may help you understand all about batteries:
- nominal tension
- discharged/charged tension
- discharge/charge current
- internal resistance
- Ampere Hours


A good site to look would be [link]http://google.com[/link] .

fox23

thank you

HJJFFFAA

You don't need to be a mod to want to keep peace. Go cause trouble on another forum.

dacaur

Since when does efficiency apply ONLY to motors? Efficiency is basically the ratio of input to output. I don't recall seeing in the dictionary the words "heat waste"... Im going to take an rc airplane as an example because the amp draw is much more consistent than a car. Its a known FACT that you can have an 1000mah NIMH or nicad pack, and a 1000Mah Lipo pack, both of similar voltage and in the same plane with no changes other than battery, you can fly for a longer time with the lipo pack, considerably longer, because it has less voltage drop under load. In order to do the same amount of work, (fly the same airspeed) the higher your volts are, the lower the amp draw. The ONLY change is the battery pack, both batteries hold the same mah, yet the lipo flies longer. So, if efficiency is the ratio of input to output. And input 1000mah to both battery packs, and the output is a longer flight time with a lipo pack. What happened? The motor didn't suddenly become more efficient, because its the same motor in both tests, so the only conclusion is that that the lipo battery is more efficient.

sunco1

Ok well i reached my first problem... I loosened the slipper clutch just a little because i was sick of backflips. And well it has completely stopped moving now. When the motor turns.. The spur does to. But the car goes no where. I took apart the slipper Assembly. Saw nothing visibly wrong so i put it back together and still nothing. When i lift it off the ground it spins JUST A LITTLE. It wants to move but i think the slippers bad. I just want a second opinion on this.

Oh and you know what a burnt out motor smells like? Well i smell that. But the motor seems to work fine. The slipper pad smelled like it. Do you think the slipper clutch melted?

dacaur

Definatly. Your post kinda made it sound like you loosened the slipper, and without even driving it, it stopped working, but im assuming you actualy drove it for a while, then it stopped working? too loose slipper=melted slipper=replace it...

Aloha Flyer

Thank God I use EXPO and a wheelie bar!

giantzack

for the price to replace the servo vs a better one just run stock ones i drive my car hard and i have only went through one and im sure its because it was a defective one. i also run 1/10th slash tires and it turns them like a pro.

giantzack

hear is my mini revo

giantzack

cloudclimberhobbies.com has all the parts for the mini revo in stock

spoonrc

What after market wheels are you guys running? Something other then the kyosho's would be nice. The stocks are too unbalanced.

Nitro Napalm

Hey there guys,

I am COMPLETLY new to electric.. been running an Nitro MT2 for a long time now. Was fed up with the repairs and constant need to clean it. Moving away for a while and wanted somethingi could tinker and mess around with during the night and indoors etc.. Someone suggested the e revo vxl and with one glance i knew i have to have it. I'm just wondering with all this talk of escs and brushless etc.. is it really THAT complicated? i just want to mess aroudn and in future maybe hop it up. Is it suitable for what i want to do. Also how long does one run last until i have to charge again. Thanks guys i just need to know because its £200 over here in the UK and that sort of money could go towards a Savage XL or even books for university lol well if i could have come advice on them points and whether its actually as good as it looks.

Luvs2Bash

The battery question has been asked and answered several times in this thread, I would say you get about 10-15 mins on the stocker, depending on how you are driving it. You would want to pick up extras anyways so that you could either run longer or get it to truly fly.

As for driving this thing indoors, you need a lot of room to be able to do that, even though it is a mini. It's just so fast. Maybe you live in a dorm with a long hallway or something like that, you could run it in something like that.

It really isn't complicated at all to use. If you aren't using lipos at all, it is very simple, just plug and play. If you are using lipos, you just have to turn the ESC to the mode where it senses the amps left on your battery so you don't deplete your lipos too much. That is as simple as holding a button down for 10 seconds. If you want to change motor or esc parts, that is a whole different story.

And yes, this thing is pretty amazing. The only thing I have spent money on since I bought it (other than batteries) was to buy heavier shock oil and I will use different springs in it when I decide to actually order them. That and buying new body clips to replace the ones that seem to disappear because you are on the lid a lot. So I've spent like 6 bucks on the oil and that's it. This thing is solid.

micro guy

Ok well i just finished a full run with mine! It was really fun! This was the first full run i have gotten in due to weather, darkness, and it being broke. So anyways i took my temp gun to it. The motor was 151 degrees, esc was 127 degrees, and my batteries were both 122 degrees. Is that too hot? I am running two batteries with the series connector and the speed pinon. Please help. I am thinking of putting a heat sink on it. But where can i get one that fits? I just want the heat sink, not the fan.

Aloha Flyer

ALL THE PARTS for the E-Revo VXL?.......cloudclimberhobbies.com . This is quite a claim. Well I needed to check. First, it's hard to specify a search on the Mini E-Revo VXL (since you end up with all the traxxas parts). Your best chance is to search under
"ERV". What do you get for your search. 38 HITS! Mostly tranny and suspension parts. You need a motor or ESC- Your outta luck. Want wheels or wings (except the wing mount)- Your outta luck. Want stock batteries and the other
100 parts- Your outta luck. And finally, does this site have the part that sparked this discussion...Body Posts #7015? NOPE

Just don't like when people plug sites that just don't have the goods...[sm=confused_smile.gif]

giantzack

the site might not be updated but i live a block away and they had all the parts for it. im not sure if you realize but the body posts for the min revo are sold in a pack of body mounts. the only thing they dont have are the upgrades. they also have all the stock parts for the mini slash. if you need somthing call them and they will check but the site should tell u all u need to know.

Aloha Flyer

I stand corrected. Let me re-phase it. cloudclimberhobbies.com has all the parts for the mini revo in stock. Take it from giantzack, who's only a block away from it located in Canada. Since the website is not updated, all you have to do is call [/b]long distance [/b]and ask. Now that my call nearly cost as much as the part I needed.........What do I do?

I stand corrected again! When you said "the site should tell u all u need to know."............Your Right, this site did tell me all I needed to know

peelin_out

So I caved and bought a revo also... selling of my MRC and some other stuff to make room in the garage... going to pull the servo off the slash and run twin servos on the revo and get a hitec for the slash servo.. I bet with the larger wheels having two steering servos does help on the revo..

Thomas P

JUst thought i share my setup on my Revo...

Nitro Napalm

Hey guys just wondering how many batteries i should have and what charger to quick charge it?? i don't want to play for 10 mins then have to wait till the next day to play again. Thanks in advance.

Aloha Flyer

As for me, I have 2 sets of lipos I bring on Sundays to run. They are 3s parallel and each set (not each Lipo) are different in respect to Capacity, C rating and weight (I do it to vary output and handling with each run). I do mostly bashing & speed runs. Occassionally I'll do a few laps on our short course we set up. In the end you should have at least 2 sets of batteries.

As for chargers, there's quit a selection. If you are new to Lipos, I would start with a 3-4S charger. If you plan to get into helis or big and fast planes/Jets you may want to expand upto 6-10S. I have 2 old chargers that have served me for the last 5 years; an Astroflight and Triton. Both are great for me since they have proven their longevity- you can probably find better with more features. Both are NOT BALANCED CHARGERS so I need to connect external balancers to the balance leads. You may want to get a balance charger so as not to have that hassle.

Why do I have both?
1. It's worked for me for so many years so why ruin it and spend more money?- Remember you can probably find better
2. The Triton charges ALL CHEMISTRIES ie Lipo, PB and NiMH. It is limited to 3S at 2.5A
3. The Astroflight ONLY charges Lipos. But can handle upto 8S at 8A. So I can charge a wide variety of Lipo capacities IN OR UNDER AN HOUR!

So what's important TO ME in 2009?
1. Choose between 4S or upto 10S depending on the type of Hobbying you want to do.
2. A Balance Charger is a convienent feature and is a plus. I'm from old school...please balance your lipos
3. I would choose a charger that can handle a rate upto 5 Amps.
4. If the charger has a flexible power source ie AC and DC that's a nice plus. Otherwise you may need to buy a power converter.
5. If you can find an all-in-one that can do suggestions 1-3 or 4[:-] and then NiMH; more power to ya!

Let me know if you want power converter suggestions

Nitro Napalm

[] I'm afraid i did'nt catch any of that. When i said i was new to electric.. i mean REAL new.. so new that i don't even know what a lipo is. I know alot of you are going to get really annoyed with me at this point.. sorry [&o]. I feel like the guy that walks into a comic book shop and asks whats the difference between dark and normal batman.

Aloha Flyer

NITRO NAPALM start with my post that came in a second before yours