It's all about gearing. You could run 2s if geared low enough.

Most people recommendations to run 4s+ on anything larger than 1/10 scale stems from the typical 8th scale weights, along with typical 8th scale speeds (35-45mph). Obviously, drive style, ESC settings, and terrain all play very large roles in how any setup will run.

A truggy basher running the "recommended" 5s-6s on a 1800-2200kv motor could still experience temp issues if they treat the trigger as an on/off switch, while running in grass, with max ESC setting (100% punch control, highest timing, etc), geared for 50mph+.

While a truggy racer running 3s on a 2600-3300kv motor could be fine because they feather the throttle, run on a well groomed track, with moderate to conservative ESC settings, and are geared for 30-35mph.

Just like 1:1 cars: A Honda civic (for example) driven by a grandma who can't even make the gas pedal reach the floor, will most likely last far longer than the same car driven by a lead-footed kid who treats each red/green light as a drag race.

Is the 3s setup in a truggy "ideal"? Maybe not, but I wouldn't call the poster a liar because he stated his experience. He could be a "grandma" driver, and the rest of us could be the lead footed kid.

I have been running my SC8E on 3s 8000 with a Neu 1515/.5y/S with a Losi Heatsink 14T pinion.Its running the same temps as my 1515/1.5D/F ON 4S 6000 15T pinion.I also put a fan on the motors.And the MMM fan comes on but never gets as warm as the motors.Its the Battery that shows signs of heat with the 3s setup though.

haha we all talk about temps and temps and temps but honestly after two years of racing 1/8th electrics and building/setting up over 14 1/8th scale cars the BIGGEST varition ive seen in temps is just handing the remote to someone different....


GREAT example, i setup a Losi8 the other weekend with a MMM, $40 ezrun 2350kv motor, and 4s 5350 pack geared for over 40mph, and the ezrun motors have those HUGE fans on it, i let the guy drive it around for 10 minutes and he never broke 120 on that cheap motor or 100 on the speedo and it was 95 degrees out side, he gave me the remote for 2 mins i had the temps up to 165 on the motor, 145 on the esc, and 125 on the lipo...... in 2 mins! i gave the remote back to him and he ran 5 more mins before it started to slow and when he pulled it off the temps were back down at 125 motor, under 100 esc, and right at 100 lipo......

i personally run 5s in my truggy and after a 6 mins race im at 160-170 on the 1515 2.5d motor and 140 on the mmm and 110 on my rcm lipo, so if a setup works for you doesnt mean itll work for someone else, i drive the hell out of my truck every time it touches the track, i have the track record at 3 tracks in the state with it and run those kinda times every race, but when i hand my radio off to others they could run it for over 20mins and temps would be low, with me driving i cant run more than 10 at my race pace....i can also tell a HUGE difference in runtimes my gf drivng my truck can run it for over 25mins on the track while i can dump the pack in under 14 now....


what im getting at is yea you could make a 3s setup work, but if your buying a system... go low kv and high voltage their are no down falls. if you already had a mmm and 2650 motor laying around im sure you could run that in a truggy fine on a PAIR of 3s in paralell with fairly low gearing.... but dont purchase a system with the intention of running 3s...

:rofl: thats a good way to put it brian, my driving style is FULL throttle, FULL brake, if your not on one or the other your not going fast enough :yes: the basic idea behind my racing style is to get in,through, and out of the corner as fast as possible, how does the saying go straights are for fast cars and corners are for fast drivers....:yipi:

Well, I don't really want to jump on the guy, but I just can't see temps being that low under conditions that are anything remotely considered normal... granny driver would be the right way to put it, and geared for maybe 30mph tops, maybe something like 25. :lol:

This is actually interesting me, I am going to test my Revo out, and see 'what is takes' to keep the motor temps to 100F on a typical summer day.

jsr, can you please posts your truck, compete setup, gearing, batts, etc? thanks, we should all know this, it's very important me thinks in hindsight.

....y?

Truggy on 4s is a minimum for me.

Btw. These motors are designed to be most efficient while running 30-35K rpms.

I vote against 3S also and say 4S min. Fans can do wonders to temps though. Maybe thats how JSR keeps his motor so cool. I can keep my Feigao 7xl ice cold with 2 40mm fans and the novak heatsink. I've run it for years now without issues. Without the heatsink and fans it would not have lasted a single run. I was easily reaching temps of 170 without much effort without any of that stuff. 3S is something we used to talk about in the day when there were no such thing as 4S controllers and people experimented and came up with 3S just being too low a voltage for a heavy truck running a descent mph. I am having a bit of trouble though with the controller being at 80 to 90 degrees on an 80 degree day. Even my best MM on 4S got hotter than that with a 40mm fan on it. I would be interested to see if JSR is running any fans on his esc and/or motor to stay that cool.

Do you guys remember my Quarkinstien? That thing ran about 10F above ambient, but look at it! :lol:

http://picasaweb.google.com/SethHuls...31438369440434

Wow, for people who have never run this setup, or a similar one, you're all very undeniably correct in your opinions.
Some info on my truggy/setup/track:

TTR ST-1
Geared for 35mph (right now, need to pick up other pinions)
Weight w/o batts ~7lbs (complete with BL setup, wheels, tires, etc.)
Batts - don't recall the brand, but each pack is rated for 90A and I run 2 packs in parallel for 180A constant discharge capability
Fans - fans are installed directly atop both the ESC and motor. They keep both quite cool. They will thermal shutdown if the fan is not used. The fans do wonders for this setup.
Track - hard packed dirt, very tight turns with many jumps (mostly small, some quite big), front and back straights that are long enough to allow about 2sec at full throttle.
Usage - I DO NOT RACE. I go to the track for fun. I don't attend during the race days as it gets quite packed. Everyone at the track is just there to run and have fun. No one during those times are very good drivers. On the straight, the BL acceleration keeps up with the nitros. Only an 8ight 2.0 pulled on me on the straights. I can out-jump him as the track is tight and doesn't have much room to build up speed (and thus rpms) for a nitro. Full throttle and full brake doesn't work well on this track. The light dusting of dirt atop the hard pack often makes you slide (although I've never tried holeshots).

If you race, I'm sure your temps will run higher. The A-Mains are usually longer than the 15 minutes that I typically run. Also, considering my track has many tight corners, full throttle is rare. It's a burst of throttle here and there and part throttle through many portions of the track.

The OP asked whether 3s can be done and everyone just follows suit of the old adage of "no way in hell", regardless of what experience, or lack thereof, they have with a 3s setup. I'm simply speaking from experience that YES, it can be done and can be done without everything exploding destroying half the planet. I already stated in my first post that it is not ideal, but it can be done without worries. If that bursts your bubble that 3s is the end of world in a truggy, sorry. Fact doesn't always follow theory.
And also, friends that run Medusas run hotter motor temps than I do. I ran geared for 40mph during bashing and they get higher temps. Don't ask me why. Their motors are "supposedly" more efficient than mine, we're all geared for about 40mph, and they typically run hotter (everyone on 4s). And at bashing, we're all full throttle.

i just dont believe u can outrun nitro on 2 3s packs in parallel that right there is alot of weight especially if eack pack is rated for 90 amps of discharge, and u said the track is tight so ur on and off the throttle alot which is going to cause more amp draw, i dont know as much as others here but am i making a good point?

The short straights may help in my favor as the nitros might not be hitting full tilt during that time. The only one that's pulled on me thus far is an 8ight 2.0.
When I'm on/off throttle, I'm not hitting full throttle. A lot of it is partial throttle which won't draw the same surge currents as a full throttle pull. The only times I can hit full throttle is entering the straights and two jumps, of which if I don't exit the previous corner right, I can't hit full throttle either. Faster throttle changes will result in higher surge currents and more ringing (residual current bounce). Slower throttle changes don't cause as much overshoot.

So 3s + fans = success...

I knew there was a reason you were able to run it on 3s without thermaling. I have seen a few 1/8 buggies run 3s with the mmm/2650 combo and they did fine.

Are all of your friends that run medusa motors using fans on the motors? I am not really impressed with medusa motors myself, but they are better than a chinese 2 pole motor. Just the design alone.

i did not see the fan part either, its great the fans keep everything under 100 degrees when they would thermal without, ummm, but whatever works, different strokes for different folks, but im done with my 2 cents and being an ass,lol it just doesnt click for me but i dont know why u would so strongly defend BS if it was not true. so ill give the benifit of the doubt.

Yeah, sorry, I run fans on all my electrics. I make that as a must. They do make a huge difference. My friends do run fans on their Medusas. I prefer 4s, but my 3s are more reliable than my 4s.

After reading his setup, and realizing that i know him in real life and i consider a goto guy on all things BL, i know this to be fact as well. Johnny sorry i called you out the way i did, I did not realize it was you posting here SORRY. YES he can run this setup it is FACT.