Can someone explain me???

Hello my holly teachers, :005:
You have to explain me something your motor choices and gearings...
Is there an affordable way to go fast with the Robinson Racing slipper and its large range of spur gears' teeth number ??? Why do you all run 44 to 51T spur gears???

My feigao 540C 9l is rated at 2730 rpm, therefore it goes hot pretty quickly with 14cells+ 16 to 18/66 ratio... (i use lightning diffs)
I love my actual crazy top speed and torque, but it runs too hot, you always say that when i tell you that i run it about 90°C... but what i want is speed and torque!!! The thing that i'm sure is that i will go soon to lipos, and i will not have 500$ to spend in a high end motor + controler.

At least, do u think that it can be better with a specific cooling system? I thought to work on a homemade cage where to fix some fans...

Sorry but I NEED TO KNOW !!! :035:

Thanks to all for sharing your precious knowledge, and sorry if i'm not clear when i post here... :( poor alone french guy...
Fab.

[BrianG]

We run 51T spurs because that is the Ofna spur that fits on the strobe slipper and they are Mod 1, which is a little beefier than 32p/0.8m. Some use 40T because it is also Mod 1 and a good gear size for the Revo/Jato.

As far as motor selection, the bigger the motor, the more torque but less Kv it will have for a given wind (turns). Small motors can't dissipate the high power levels needed for heavier trucks. So, if you have a heavy truck, you'd want to go with a large motor for the torque and simply increase the voltage to get the speed you want. A larger motor will also handle taller gearing because of the added torque. You could go with a very low turn large motor to get the high kv, but then the current requirements would be a little ridiculous. It's generally better to get a high turn (lower kv) and use higher voltages for greater efficiency.

Think of it like a 4-cyl, 6-cyl, and 8-cyl in 1:1 cars. A 4-cyl works well in a light vehicle while maintaining light weight and fairly high gas mileage (efficiency). You could put a v6 or v8, and it would go faster, but you are barely using the power and efficiency would suffer due to the inherent losses in friction. Similarly, you don't want to put a 4-cyl in a big truck. You'd have to gear it so it would rev high and still go fairly slow because of the missing torque. And you'd still be stressing it so efficiency would be less than a v8 properly loaded.

[neweuser]

I would try dropping your teeth in the pinion. But from my understanding, the 9L runs hot. Try a 9xl? But if your running low cells, maybe an 8xl?

ok i understand... is there any alternative to the feigao, but at affordable price on the market?

[AP Alex]

I run a fan on my speed controller and my motor. The fans help alot with the heat. Gearing down will also help.

[neweuser]

Well, you pay for efficiency. The wanderers/faigos/nemesis motors are your best bet. If you want a dependable sytem. Sure, there are other options, but most here go with what they do because they are good systems. Dependable. The question really is, how often do you want to KEEP dumping money into your system? Once, twice, three times a motor or controller?

[squeeforever]

A Feigao should last the life of the truck if treated properly. Bearings are your only thing to go bad and should be replaced every so often. Not really that big a deal though. Not like cutting a comm every 5 runs :p. Anyway, I would always recommend a Neu or a LMT if you can afford it, but a Feigao C XL is the next best thing. I personally can't wait for the new Lehner XXL motors to be released...

[Re~Mix]

On top of all this, the 9L really shouldn't be ran on more than 12 cells, because then it just becomes a heat problem where other efficient motors would gain more power.