Typhon Typhon Brushed Mega upgrade to 4s gearing problems.

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DesertRCLife

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Arrma RC's
  1. 4x4-Mega
So I have the brushed version of the Typhon, already swapped the electronics with a Spektra set I owned. Spektra 120amp 4s smart ESC+ Spektra 3150 brushless sensor less motor. I'm not getting the gearing ratio correct because even on 4s my top speed was only 57mph. My esc never climbed above 150°F but my motor can ive seen upwards of 180-200°F using an infrared temp gun. Any suggestions on gearing ratio I should be using. I had 24T/36T Mod 1 gearing when I got to 57. But those temps clearly indicate that's wrong lol. I was able to replace the slipper with an eliminator using the Revo's spur gear (no modification needed). Should I be running a big gap as far as Pinion to spur ratio, or smaller? Or should my pinion have teeth than my spur gear? I've seen a cpl videos on youtube with this done and they reached speeds of over 100mph which ultimately is what I'm trying to achieve as well. Thank you in advance for any and all suggestions.
 
I think you're geared waaay too high. Your electronics can't handle the load.
Do you have any suggestions? Should I be using .8 mod or is mod 1 better? Im still baffled setup it came with..I thought for sure it would be .8 mod. Had no idea the pinion from my 1/18 ecx would mesh up with the spur of 1/8 Typhon Spur gear lol.
 
I’m running .8 mod without issues. Same setup as a 3s BLX. You will go through spur gears more often on 4s. At least the diffs are the same As the BLX. That was not always the case. Mega used to come with lower end diffs. Input gears would snap as they were all plastic.
 
Do you have any suggestions? Should I be using .8 mod or is mod 1 better? Im still baffled setup it came with..I thought for sure it would be .8 mod. Had no idea the pinion from my 1/18 ecx would mesh up with the spur of 1/8 Typhon Spur gear lol.
Assuming 100mm road tires, you’re geared for well over 100mph with a power system that can’t handle it. Pic below.

You may have to play around with pinions a bit. I’d try gearing for ~80mph to see what happens.


1673291851187.png
 
130 amp Spektrum Firma can and does run 4s. As you saw. I think that there are typos in that listed above.
Just that Spektrum stuff is not what you want for speed running at all. Amp overhead is slim to none as RTR ESC's go. Here, 130 Firma is only at 100 amp sustained. NG. You can work with what you got. Just don't expect miracles.
Your gearing is all wrong. Overgeared. And using Mod 1 is just fine, as long as you can dial in the gearing best. .8 mod might give you some more gearing options/ratios with a 4x4 rig. Need to use a speed gear calculator for speed running. If you plan on running a 4s pack, for instance, plug in a 3s lipo into the speed gear calculator for a better conservative speed estimate. How most of us do this. Needing to compensate for the lipo's "Voltage Sag" under hard sustained throttle.
 
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Like others say, probably geared too high & the 3s Spektrum 3150kv motor can't handle 4s @ that load.

My Outcast 4s (bigger tires, more weight) had the 2400kv motor in it, but I swapped the electronics to the BLX185 150a ESC & a bigger canned, more torque Surpass Hobby 4068 2650kv on 4s with fans...

Wheelies on demand with less than full throttle at any speed. But my 4s lipo packs get too hot with a 15t pinion.

ESC & motor have aftermarket fans & temps are in check. So maybe I'll gear down a lil & try a speed run on Talion wheels. Just to see what it does.
 
Didn't realize I typed 120amp me t 130 amp, but when I purchased the motor and ESC the hobby shop confirmed both could handle 4s..guess not..I do plan on upgrading to 6s. Just received my new motor 2days ago. But still have lots to upgrade.
Assuming 100mm road tires, you’re geared for well over 100mph with a power system that can’t handle it. Pic below.

You may have to play around with pinions a bit. I’d try gearing for ~80mph to see what happens.


View attachment 268544
Can I ask what program/app this 8s to get this info? Ive tried several gearing apps in the play store, but nothing as detailed as this
 
Didn't realize I typed 120amp me t 130 amp, but when I purchased the motor and ESC the hobby shop confirmed both could handle 4s..guess not..I do plan on upgrading to 6s. Just received my new motor 2days ago. But still have lots to upgrade.

Can I ask what program/app this 8s to get this info? Ive tried several gearing apps in the play store, but nothing as detailed as this
The app I use is Apple only I believe. I’ve seen @Moirae recommend a website but I can’t remember it right now.
 
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