Ryan,

You will want to pick up an idler gear for the transmission eventually. The stock one will last until you get the rest of the drivetrain beefed up (cvds, diffs etc.), but once everything else stops breaking, this is the next weak link. They aren't that expensive, either. There is a thread on this board with a link to the part you will need.

Hey Ryan


Idler - Here ya go

http://www.unlimitedengineering.com/...ore/13407.html


:) :)

Havent touched the tranny yet. Well I was flying down the road and spun out of control and slid into the curb. Now I need to get a new chassis, bulkhead, turnbuckel, and shock. I new it was just a matter of time.

Curbing....
 

Thats how most of us started our projects - bash HARDER, break FASTER, break MORE, then replace, replace, replace with stronger - then repeat..... LOL - But then thats the fun of it in my opinion, - comparing it to a stock emaxx and see how much you've done and how much faster and more durable it is. It is definately worth it for me and probably to most of us as well... It IS a sickness ya know :) :) :)

50 mph for emaxx ain't all that hard. Top speed has NOTHING to do with weight. Weight just means it'll take longer to get there. Top speed has everything to do with max power of batteries - NOT the motor you're running.

A puny little basic 4200 can push an emaxx beyond 45 mph on only 12 cells - I know, I've done it.

A monstrous lehner 2280 on 12 cells will only push it around 45 mph also. Why? Because 12 cells can only give out so much power continouosly.

14 cells could hit 50 mph, but only for a couple of speed runs. 16+ cells would be needed. IMO.

At 50 mph, you need to stiffen suspension, lower chassis, and get better high speed tires or duct tape the insides of the tires to prevent excessive ballooning. Stock tires actually spin truer for me than most ProLine tires that I've come across.

Lipos is an easy way to get to 50 mph w/o much mods. Lipos are much lighter and so easier on drivetrain. I'm going over 50 mph with my lipos and doing it over and over and over on the same charge. I'm getting huge run time, very little heat, and awesome response with my STOCK emaxx running lipos. BUT, you have to be VERY CAREFUL WITH LIPOS.

I agree with the previous post, but would like to add to it. While a high top speed can be reached with a small motor, the motor will eventually fail if it is driven this hard continuously (I have "failed a few motors"). For continued high speed, a larger motor can dissipate the heat better and will last longer. Higher voltage (like Lipos) will also help keep the heat/amp draw down, which may also lead to increased reliability (as long as the motor is not over revved). I will also say that weight may not be a big factor, but it is part of the equation. It takes more energy to move more mass.

Energy = 1/2 mass x velocity^2
So yes, weight will use more energy to go faster, but velocity itself is the larger factor. Now, with RC cars, you have to add rotaional energy to this equation - I forget the rotational energy equation though.

With regards to small motors failing, Mike is right. A motor can only run as hard as it is able to dissipate heat. A huge motor that is insulated will fail, a small motor with good heat sinks and good cooling might be better.

Every motor has its inefficiencies. Let's say motor A is 80 percent efficient and motor B is 90 percent efficient. Let's say a motor can dissipate about 100 watts of heat. Motor B can handle 2x the power input than motor A!

That's why it's so important to get efficient motors. Brushed motors are less efficient and will run much hotter with less power input so that's one of the reasons why BL can handle more power.

Now, a typical small wind motor will be less efficient than a high wind motor (case in point, a Lehner Basic 5300 vs. a Basic 3100). Both motors are the same size, but the Basic 3100 is much more efficient. So, instead of using 7.2 volts with the 5300, I'd much rather go 11.1 or 14.8 volts with the 3100. Equal power, but much more efficient so less heat build up, more CONTINUOUS power.... blah blah blah.

So, I'm just saying get good cooling, good heat sinks, get a really efficient motor (but slow) and use high voltage and low amperage. You'll really have gobs of power, speed, and run time. Why do you think the Heli guys are going 10S lipo? They've already figured it out for us.

If you look at Lehner's brushless motor dyno charts, you'll see that for the basic motors, slower than the 3100, efficiency doesn't really improve so you don't need to go slower and higher voltage than 22.2 volts. However for monster trucks where amp loads can be very high, going even lower KV and higher voltage pans not because of gain in efficiency due to motor, but gain in efficiency due to lower amp draw through controller and wiring. Now I'm talking too much...

Yeah, what he said! great tech info lipomaxx! I have some slow motors intended for just this type of thinking on the way (1200 rpm/volt, 1600 rpm/volt). My plan is to use them in a lipo e-maxx with 6 or 7 lipo cells. I haven't decided on which ones yet, but as you already mentioned, the polyquest line of batteries seem to be high quality.

here is a HV setup discussed. (tried and tested to)

Lipo will be the new breed. (holding the hand firmly of brushless)

And a higher voltage will also be suffering less from the internal ressistance.

for that reason electricity we have got in our houses is transported at several kvolts. (thru 'high resistance' aluminum wires.. )


In small words; At higher voltages it's easier to be more efficient.

Actually, aluminum wiring has less resistance than copper... if you go by weight! That's why high voltage cabling is aluminum. Copper will sag too much because it weighs so much, same with silver. Aluminum is like 3x lighter but 2x more resistance (those are gross approximations) so there is less sag of the wires when stretched out over long distances.

You're right in that. I smell a bit of a scientist here..

I have got the same discussions with my brother in law, he's a scientist to. (discussions in the most possitive way)


Aluminium has got a higher resistance then copper per square inch.

And a high voltage system will be eassier more efficient then a low voltage system

No, not a scientist - high school AP physics and experience.

isnt the 8L only suppose to be run on 12 cells?

HotnCold doesn't run full power on his radio. I have run the 8L on 14 cells a couple times without any trouble, but it isn't recommended.

throttle
 

60-65% to be exact -