Gruber
HobbyMasters
M.L. Toys
KidsWheels
Gruber
HobbyMasters
M.L. Toys
KidsWheels
HobbyMasters M.L. Toys
Gruber
KidsWheels
Need new motors? Grind a gearbox? Adding teeth to a pinion?
By Oakstone
#149151
Heya,

I went up to 18v in my Dune Racer and wanted a brake reduction module to help ease the strain on the drive train. But, I also wanted the kidlet to be able to do skids when it was slick and raining out. So, I tested various resistor amounts to see how many ohms affected the braking. While “up on blocks” in my shop, 5 ohms seemed to start adding brakes back in vs. a cut brake wire (no brakes). So I ordered a 5w 5ohm pot for about $7 from Digikey. It works well but I am going to put a 5ohm 5w resistor across the pot to make the effective range 0-2.5 ohms, since the top 1/2 of the pot doesn’t have very much effect. It’s been fun to do and the driver likes having a brake amount knob so I thought I’d share. ;)

Potentiometer - https://www.digikey.ca/product-detail/en/203771

Resistor - https://www.digikey.ca/product-detail/en/4135362

There’s 3 terminals on the pot. Cut the orange brake wire, I did it right next to the gear shift since it was easy to access. Connect the brake wire to the middle terminal and one of the outside ones. There’s no wrong terminal, left or right, for the second connection. It’ll just make the knob increase or decrease braking power in the opposite turning direction. If you don’t like the direction, just swap the outside terminal connection.

Once you’ve picked terminals, just solder the resistor across them to reduce the total resistance to 2.5 ohms.

Hope someone finds this cheap little mod useful!

I’m doing a turbo button via relay tomorrow, wish me luck haha

Cheers!
#149237
Thank you so much for this idea! I was just going to put a switch in but this is a much better solution. The links you posted no longer work. Do you have the part number and/or do you think either of these would work?

https://www.amazon.com/dp/B074KCK7X9/?coliid=I24I9WMW50PRBO&colid=2QV30H9TEFLUH&psc=0&ref_=lv_ov_lig_dp_it

https://www.amazon.com/dp/B074KC1FY4/?coliid=I3GD1MSFZQ6QNU&colid=2QV30H9TEFLUH&psc=0&ref_=lv_ov_lig_dp_it

Also how are you going to run the "turbo"? I was going to use this DPDT relay so that I could go from two batteries in parallel and with a push of a button switch them to series.

https://www.amazon.com/gp/product/B00REFBL7A/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I was also contemplating using a timed DPDT relay so that my son didn't burn up everything before I upgraded the motors/gearbox.

https://www.amazon.com/dp/B01IEQC5GS/?coliid=I16AA8QUL7QJTX&colid=2QV30H9TEFLUH&psc=0&ref_=lv_ov_lig_dp_it

Thank you for your help and let us know how it turns out and we would love to see some pictures!
ESC vs Drill trigger

Pirsen, how could you use a pedal, does any instru[…]

So many options for the 775. I want to leave the […]

Battery questions

Just got 2 free power wheels. 1. Jeep has origina[…]

Looks like I got into this whole modded PW thing s[…]

HobbyMasters Udemy Course