dex410 gearing

jake1*2011 · #1 10-02-2013

wander if anyone can help, I've got a 5.5 turn motor in my 410 and at the mo Im running a 87 tooth spur and 21 tooth pinion, which the motor and speedo are running quite hot, hot enough where you can't hold your finger on them for more then 3 seconds, what gearing should i use to eliminate this problem? Should i be thinking of changing the spur?

IrishRacer · #2 10-02-2013

I would put a decent fan with a good heatsink on the esc and on the motor I saw on fastrax they have a heat sink for your motor with two fans on it. I wouldn't think there should be a problem with the spur gear but I know a fella in my club who has a 7.5t motor and he is using a 27t pinion gear.

Thanks a mil
IrishRacer

jake1*2011 · #3 10-02-2013

Someone at the club suggested going to 18 or 19 tooth pinion, should i try that aswell?

mattr · #4 10-02-2013

1) get a temp gauge, perfectly safe temperatures for the motor/esc will strip fingerprints off and give you a nasty burn.
2) with the stock spur, I'd be looking at a 18/19/20 Ish range. Dependant on circuit. Currently running a 22 Ish on a 6.5, but quite a tight indoor circuit.
3) check nothings binding, I pushed a motor from 70-80 degrees to 130 by over-tightening all the gearbox screws

4) get a temp gauge, seriously, your thumb is a carp temperature gauge.

jake1*2011 · #5 10-02-2013

I have a turnigy temp gauge, i just forget to take it with me! What sort of temps should i not exceed? I know its getting hot enough for the speedo to cut out! Ill stick an 18 tooth pinion on

thanks for the help

mattr · #6 10-02-2013

70-80 degrees won't be too far off.
Take a tool kit next time.

mattr · #7 10-02-2013

And the fusion exceed speedo really needs a fan in a 410 (I ran one for a year or so) it overheated regularly and easily with fairly minimal load.

mattr · #8 10-02-2013

70-80 degrees won't be too far off.
Take a tool kit next time.

jake1*2011 · #9 10-02-2013

I've got a couple of high output fans laying around here somewhere, ill put one in for the speedo, is there any heat sinks that will fit into the 410 without modifications? I've had to cut and file the one I've got to try and get it to fit!

mattr · #10 10-02-2013

The esc already has a heatsink. You just need the fan.
The motor shouldn't need one. You'd struggle to fit it in anyway,
This is when you find out how well you packed all the electronics!

What are you actually using the car for?
If you are running as long as you physically can (until low voltage cutoff) you are going to struggle to keep it under the temp cutoff.
I tend to restrict myself to 8-10 minutes at a time. I could run for 15, but that cooks everything.

jake1*2011 · #11 10-02-2013

Its a very tight fit but i think ill get away with it!

I use it for racing at the local track, its a tight track with a 75-100 foot straight, its about 5 minutes per heat. Sometimes ill take it to the school field or work for a blast but i make sure its a couple of days after they've cut the grass and again about 5-10 minutes per battery with a 10 minute rest in-between.