Typhon arrma typhon 3s on road gearing

[diegov88]

Hello, ive been running my arrma typhon 3s on rally on road form, changed the motor to a surpass hobby 3600kv 3660 size motor and

stock ESC, my question is gearing wise, im planning on running 2s lipo 5200mah 80c 21t pinion 57t spur, would the electronics

withstand the high gearing for some onroad racing, anyone running a setup similar to this?

 

[Tex Koder]

View attachment 324576
Hello, ive been running my arrma typhon 3s on rally on road form, changed the motor to a surpass hobby 3600kv 3660 size motor and

stock ESC, my question is gearing wise, im planning on running 2s lipo 5200mah 80c 21t pinion 57t spur, would the electronics

withstand the high gearing for some onroad racing, anyone running a setup similar to this?

Drifting in a Dam spillway!!

 

[diegov88]

Drifting in a Dam spillway!!

the dam is in half capacity so no worries

 

[Jerold]

What is your goal?

If you want top end speed it may help. If you want acceleration it may not because it takes more torque to turn the big pinion. A larger pinion will also reduce your run time.

I think the stock pinion, like 15T? If which means 15T to 21T is a pretty big jump.

There are two pieces to this. The motor temp and physically fitting in the car.

The motor temp depends on the gear ratio. Big gears take more torque, which requires more Amps.

It looks like your wheels are smaller than stock. Amain shows the stock tires as 117mm and it looks like you are running GRPs, which would be 100mm. If so you're getting a gear reduction there.

The pinion is +40% and the tires are -15%. Which means your net is really more like +25% on gearing. Which is still a big jump, but running 2S is much less stress than 3S or 4S so it's "possible".

Assuming my tire assumption is correct an 18T pinion would be a touch more gearing that stock.

As for fitting the gears, I have no idea. But there is a thread on Typhon gearing, where several people said the had 19/50t pinion/spur.
https://www.arrmaforum.com/threads/help-understanding-gearing-for-a-typhon.11017
https://www.arrmaforum.com/threads/tlr-typhon-gearing-suggestions.44469/

The final result will depend on your specific setup. You can try it out, run it for a few mins, see if the motor is hot, then repeat. Motor temp is really the problem. If have a large pinion it's more stress on the motor, ESC and batteries. Something will get hot if it's too much.

Do small steps, check the temps.

 

[Neelis]

Running 3s with a 17t pinion in grass doesn't really work, motor overheats before the battery pack is empty. On road it was fine.
On 2s the motor will overheat less fast, so you might be fine. It is really a matter of trials and error, I don't think many people here run high gearing on 2s.
As said before, keep an eye on temperatures.

I did see speed runs on 3s and 21t pinion doing almost 100kmph.

 

[K-BASH]

No it'll cut an overheat..you want lower kv like 2050kv or a bigger esc

 

[Neelis]

No it'll cut an overheat..you want lower kv like 2050kv or a bigger esc

2050kv to run on 2s?

 

[K-BASH]

2050kv to run on 2s?

Yup,thats only way youll do what you wanna do with stock esc on 2s without overworking system..would need like 30/30 gearing to get 50 mph thou
Stock esc an 2050kv 6s motoran it'll run theou grass allday ...stock 100a esc an 6s 2050kv motor run great together..heres my vendetta on 2s..worlds fastest

 

[Neelis]

Does that have to do with the max power the motor draws (for example 1500 watts), the voltage of the 2s battery and the amps the esc can handle?

A 120A esc runs max 1000 watts at 8.4 volts.
A 150A esc at 4s is about 2500 watt. (I am thinking out loud, you seems to have a good understanding of this).

 

[Jerold]

Does that have to do with the max power the motor draws (for example 1500 watts), the voltage of the 2s battery and the amps the esc can handle?

A 120A esc runs max 1000 watts at 8.4 volts.
A 150A esc at 4s is about 2500 watt. (I am thinking out loud, you seems to have a good understanding of this).

Your math is correct, if you are running 2S (8.4V), then your battery(s) should be able to source 120A continuously, which is ~1KW.

However, it's quite not that simple. Generically I would use a bigger (more Amps) ESC than you think you will need and back that up with even bigger (mAh) batteries. This reduces the bottle necks and never starves your motor for current. The system is only as strong as it's weakest link.

If your limited on Volts use more mAH. That's why the drag packs are configured as 2S6P, for maximum current.

Your Motor can only pull as much current as available from the ESC. And the ESC can only pull as much current is available from the batteries. More amps doesn't make you go faster if your motor can't use it. But a lack of current will reduce your performance in the form of voltage will droop, and cause less RPM at the motor.

The thing to remember is that the 120A is most likely not maximum, it's the continuous current. Similarly your motor has a continuous and maximum current. Find those and size up at each step.

The problem is, as a system the Amps can be calcuated but it's never whats on paper. I have TP3640 motor that is spec'd at 3KW max power. Yet I've pulled nearly 250Aon 4S (16.8V) which is about 4KW at the ESC.

If you want to go fast, start with an oversized ESC and back it up with an over sized ESC.

 

[Tex Koder]

the dam is in half capacity so no worries

So if the dam goes to near empty..

You'll have BOTH a nice ramp for distance AND a Perfect Vertical ramp to Send it to the Moon!!!

 

[Neelis]

Your math is correct, if you are running 2S (8.4V), then your battery(s) should be able to source 120A continuously, which is ~1KW.

However, it's quite not that simple. Generically I would use a bigger (more Amps) ESC than you think you will need and back that up with even bigger (mAh) batteries. This reduces the bottle necks and never starves your motor for current. The system is only as strong as it's weakest link.

If your limited on Volts use more mAH. That's why the drag packs are configured as 2S6P, for maximum current.

Your Motor can only pull as much current as available from the ESC. And the ESC can only pull as much current is available from the batteries. More amps doesn't make you go faster if your motor can't use it. But a lack of current will reduce your performance in the form of voltage will droop, and cause less RPM at the motor.

The thing to remember is that the 120A is most likely not maximum, it's the continuous current. Similarly your motor has a continuous and maximum current. Find those and size up at each step.

The problem is, as a system the Amps can be calcuated but it's never whats on paper. I have TP3640 motor that is spec'd at 3KW max power. Yet I've pulled nearly 250Aon 4S (16.8V) which is about 4KW at the ESC.

If you want to go fast, start with an oversized ESC and back it up with an over sized ESC.

Clear story, but the part I don't really understand is the advise of a 2050kv motor for a 2s setup. For onroad racing I would expect a 5800kv motor to be recommended.

 

[Jerold]

Clear story, but the part I don't really understand is the advise of a 2050kv motor for a 2s setup. For onroad racing I would expect a 5800kv motor to be recommended.

We still don't know if you want to speed run, bash, street race, drift....?

Trust me @K-BASH knows what he's talking about. He in the triple digits every day on every platform.

There's always a trade off between RPM and torque. A high KV motor is more RPM and lower torque. Which means pushing the gearing up will strain the motor/ESC more because of the lower torque motor's ability to turn the large gears.

Spinning at 5800 RPM with no torque left in the bank won't make it faster.

If you want to go top speed fast, you're better off with more torque and gearing up vs more RPM and gearing down.

 

[K-BASH]

Clear story, but the part I don't really understand is the advise of a 2050kv motor for a 2s setup. For onroad racing I would expect a 5800kv motor to be recommended.

Your right,but with 100a esc it'll just be to much...size of motor means nothing..its all about rpms..takes alot more energy(esc) for 5000kv than for 2000kv..all my cars tequte xlx2s cause im running higher lv motors. Like this 40×74mm 5600kv must have xlx2 or it'll be to much for any other esc

 

[Neelis]

Your right,but with 100a esc it'll just be to much...size of motor means nothing..its all about rpms..takes alot more energy(esc) for 5000kv than for 2000kv..all my cars tequte xlx2s cause im running higher lv motors. Like this 40×82 5600kv must have xlx2 or it'll be to much for any other esc

View attachment 324769

That setup is mental!
You run that on 2s?

 

[K-BASH]

That setup is mental!
You run that on 2s?

2-4s..

 

[Neelis]

5600kv and 4s
Dude....!

 

[K-BASH]

This 5600kv motor turn 33,000rpms on 2s

5600kv and 4s
Dude....!

70,000rpms on 4s lol