vios8820

because i just buy a hW combo set for my rc18t which is

18A + 7800kv motors..

well to day i just saw this

http://cgi.ebay.com.my/New-8900-KV-B...item2303bdb7c1

DAMN IT SO FREAKING CHEAP !!!

30a is alot more power than my HW brushless system..

any review on those cheap esc yet ? i know it use on plane or heli.. does it work well on rc car ?

and my some newbie question...

for 18a 7800kv motors if i set to punch level 1 ...
with 1700mah lipo battery how much is the run time ?

i new in 1/18

Snipin_Willy

1700 will (should) give you more than 12 or 15 min of racing, but it depends on you driving and your gearing. I'm not sold on the quality of these off brand EBAY motors.

Cheap Guy

I actually have a couple of those "no-name" combos, exactly like the one you posted, from the exact same seller, running them in my Pro-Pulse T100s. I got them for less than $25 each by careful bidding.

Compared to the EZRun combos, the lower quality is noticeable. So far they are holding up and are working fine, but they just feel and look cheaper. I ended up trimming the plastic covering on the ESC to give it a little more airflow. Having said that, the combo has performed flawlessly, other than the fact that I still haven't been able to program it with the directions provided by the eBay shipper.

I initially tried the 8900kv combo in my Mini-T and the power made them practically uncontrollable; in fact, without a wheelie bar I nearly destroyed my Mini-T due to the damage from high speed backflips and cartwheels. I basically had to replace dogbones, tierods, shocks and mounts and other parts, but the stock differential and tranny held up fine. On the other hand, my Pro-Pulse took everything the 8900kv could dish out, with good high speed performance (no wheelies and fewer flips) and no major damage. The speed difference between the 7800kv and the 8900kv is noticeable, but both are practically high speed run cars-only unless you are VERY careful with the throttle.

The biggest issue with these combos is that the programming is a lot more difficult than with the EZRun and you have to buy the USB programming connector separately for $8, which puts you very close to EZRun prices ($50 for the EZRun 25a/7800kv combo). Since I'm running two Pro-Pulse cars, it was somewhat cost effective since I only had to buy one programmer, but if you only have one car, I'd go with the EZRun, and if you just have to have that extra speed, buy the 8900kv motor separately.

The combo you bought should be fine. I bet the 30a claim is exaggerated. The main reason why I like the EZRun 25a ESC over the 18a is that I don't like the fact that the programming button is on the "On/Off" switch on the 18a.

Regarding your run-time question, I can't give you an exact time as to how long the battery lasted, but with two HobbyCity.com 1300mah lipo batteries, running flat out most of the time, I usually get more than enough playtime.

vios8820

thank's for reply Cheap Guy actually i going to buy 18a but rcmarts there dun have. .so i have no choice to get 18a... done 18a and 25a Big difference ? i am noob at 1/18
normally i with my 1/8 caster racing truggy.. with 150a 2000kv it bring me really lot of runtime... at least 30min... race time... also in very warn temparature

but i heard that if 1/8 that motors kv... u nid really have choose the motor wisely .. if not wrong combo will definally kills ur component am i right ?

i hope my 1/18 using 7800kv will not overheated or something

Cheap Guy

From what I'm told, the 25a isn't a big difference over the 18a. As far as temps, just be prepared to gear up/down to keep it running right. Again, you won't lose much performance since the 7800kv motor is very fast, probably too fast for a track. With the 1700mah battery, you should easily get more than 1/2 hour run time.

As far as damage, a lot of people recommend tranny/differential upgrades, but the EZRun allows for softer launches, which means less stress on the drivetrain. My damage came mainly because when these 1/18 cars get going fast, when they wreck, it usually resulting in damage to the suspension since there really isn't any protection. You may want to get a RPM bumper.

mini-dude

literally ANYhigher kv-rated motor will have heat issues, it's almost impossible to remidy and realistically, IMHO,anything over 6800 (oval racing) or 5400 (off-road) is severe overkill - making it not only very hard to drive, but severly affecting runtime (as well as increasing repair costs from running into things at warp speed)

vios8820

thanks Cheap Guy , mini-dude i really appreciated ur help... i just waitting my esc to arrival in term of heat... what normally is the motor temperature ?
i am going to set punch level 1.. just like my 1/8 caster truggy... i set on 1.. but is already super fast.. :lol:

studysession

I mostly bash than race.

I put the highest kv motor in that I can poosible afford and just have fun. If you are in an area where it is to fast then let off the throttle - then when you have a long straight - open it up and watch it fly.

mini-dude

I use the "finger test" method for testing temps = if you can hold your finger on the motor for more than 5 seconds without screaming like a schoolgirl (or suffering 3rd degree burns) you should be fine.

Cheap Guy

Ha, ha, I thought I was the only one who had that attitude! I thought about racing but I already have a stressful real job so when I PLAY with my RC cars, I just like to punch it and go, sometimes letting the dog get her exercise chasing them. I'm in the Detroit area and I found an abandoned factory (not uncommon in these parts [sm=sad_smile.gif] that has a huge parking lot - big enough that when it gets going, it's practically out of sight if I'm not careful. The only problem is if it flips or crashes, which means a long jog to get them. I'm thinking about bringing my bike for my next bash, LOL.

studysession

Cheap Guy -
I too love going to empty parking lots.
Base ball diamonds make great areas for bashing off road. I take my 18t, Leo-x, Mini-t, EMaxx or even my brushless 1/8 scale Hyper 7 PBS to a base ball field. Loads of fun for off road bashing. I also have a skate board ramp that I bought from toy-r-us that I take with me sometimes.

Yeah - put the biggest kv motor you can afford and run it like you stole it. If you are running in an area where it is to fast then just let off the throttle and all is fine. I find the higher KV motors are a lot more fun for bashing around.