Even if it WAS true...

charliebrown · #1 01-27-2004, 07:03 PM

Remember that on Ebay they were selling imported 4.8 and 4.5 motors?

Well, I talked to my LHS (Local Hobby shop, for those who don't know) clerk and he said that they weren't going to sell them. He spoke to the people who made them, and he says if you buy one it will BURN YOUR CAR. It has no torque, and it pulls more current than the cars can dish out. He says it will burn the pcb, and that even if it worked, the motor would have almost no torque.

So, there. The 4.2 is pretty much the limit. I think I'll stick with that, and the Phast motor.

Chuckster...

ION · #2 01-27-2004, 07:29 PM

A guy that works for a company told a random sales clerk that his companies product will destroy the car in which it was intended to be used for?

I wouldn't rely on that statement as being trustworthy.

ION · #3 01-27-2004, 07:36 PM

I have a follow up question...

Does the sales clerk already have motors sitting on the shelf that he would like you to buy, instead of you spending your money on ebay? I'm sure he does.

Also, I'm no electronics guy, but I imagine motors don't actively 'pull' current. They only use as much energy as put into them.

If anything, the electronics would burn up motors, and not the other way around.

theMonster · #4 01-27-2004, 08:14 PM

Sorry ION but you're wrong. I used to believe this too. Charlie Brown has learned about this from the x-mods forum. I do tend to think that the microB motors though are too small to really do any harm in the stock electronics. These things aren't as complex as the x-mods and mini-zs are. \

btw hey Chuck, did you check out my FAQ on the mini-tank I got? It's listed under "Question about my new toy" in this forum. It's pretty cool!

charliebrown · #5 01-28-2004, 09:14 AM

Quote:

Originally posted by theMonster
Sorry ION but you're wrong. I used to believe this too. Charlie Brown has learned about this from the x-mods forum. I do tend to think that the microB motors though are too small to really do any harm in the stock electronics. These things aren't as complex as the x-mods and mini-zs are. \

btw hey Chuck, did you check out my FAQ on the mini-tank I got? It's listed under "Question about my new toy" in this forum. It's pretty cool!

I responded to that thread.....check it out.

Chuckster...

MicroSpeed · #6 01-28-2004, 09:17 AM

What if you got an FET mod done to it, then wouldn't it get a little more power to the motor? Or a dual/tri cell???

ION · #7 01-28-2004, 09:59 AM

Quote:

Originally posted by theMonster
Charlie Brown has learned about this from the x-mods forum.

Mind posting a link to the thread?

theMonster · #8 01-28-2004, 01:39 PM

Sorry ION but there is just too many threads to pick one certain one out and say "here is your answer". Try going to the xmods forum on tinyrc and reading everything you can on the post topics concerning FETS and ESC. It'll probably be very difficult to understand if you are not very knowledgable about RC cars in general.

ION · #9 01-28-2004, 02:27 PM

So the conditions you are referring to is when there is electronics modding going on? And the components that are put on the pcb aren't rated high enough for the amount of electricity that will be flowing to a high performance electric motor.

There is quite a diffirence in that statement, and stating that the fastest motor to ever run safely on a bit will be 4.2. That is quite a stretch.

theMonster · #10 01-29-2004, 04:21 PM

Not just the amount of electricty (Volts) but also the current draw (Amps). A MOSFET transistor may be able to handle 5V at 200mA but if you run 2.5V through it and the motor pulls a current of 400mA, it's going to sizzle like a slice of bacon. Also note this, mA is the current draw, while mAh is the stored capacity of a battery (the length of time it will last before drained). I don't know if the statement about the 4.2 is true or false, I'm just stating that it's plausible.

ION · #11 01-29-2004, 05:37 PM

Hmmm, I see. Can a battery have a rated max mA, along with its max mAh?

theMonster · #12 01-29-2004, 07:14 PM

mA is not related to the battery at all. Think of a battery as a container. a container for stored energy to be exact. To be even more analagical let's say a juice-box. Then think of a the electronics as a straw and your mouth as the motor. The mAh is the amount of juice in the battery or "box". Your mouth is the motor pulling the juice from the container/box to itself through the straw. That's the mA, is the amount of force you suck through the straw with to extract the juice from the battery/box. There is a threshold that if you suck too hard then the straw will burst or in this case the FETS in the electronics will pop/fry.

In review:

mAh= the amount of juice stored in the battery: Like the juice-box
mA= The amount of juice being extracted through the straw/electronics by the motor/mouth

In conclusion, the only thing a higher rated mAh battery will do is cause the car to run longer. Another analogy is that an 50mah battery is like a 5 ounce juice-box where a 200maH battery is like a 20 ounce bottle. The only difference is that where the box/bottle will always be different sizes, the batteries may not.

gee....I feel like Mr. Wizard.....or to the younger folks...Bill Nye... heh, who would've known teaching would be fun?

ION · #13 01-29-2004, 10:30 PM

*raises hand again*

So if the motor had the ability to pull an unlimited amount of mA, it could effectively drain the battery in an instant?(assuming the electronic connection could handle the capacity)

newbitowner · #14 01-30-2004, 01:15 AM

i can sell a phast motor for $ shipped and/or 1 4.2 king/king pro motor for $5 shipped.

theMonster · #15 01-30-2004, 01:26 PM

That is correct Ion, that is why car batteries come in different amperages. Plus some have more cold-cranking amps because when the car is cold, it has to grind a little-bit longer in order for the started to turn-over. You could easily drain a car-battery by grinding the starter too-long with a battery with too-little cold-cranking-amps.