Rs550 electric motor help

Thread Starter

Marka1977

Joined Nov 24, 2018
19
My son has an electric ride on car. Twin 6v motors powered by a 12v battery. (12v 7ah)
It does about 3mph which is slow. I know I can put another 12v battery which will double the speed. But it risks over heating the motors.

Can I get 12v rs550 motors that have more torque and and a higher rpm? I know I will need the second 12v battery as powering 2 12v motors will need 24v. Or would I be better getting 2 6v motors with a higher rpm and torque?
 

Thread Starter

Marka1977

Joined Nov 24, 2018
19
I have, but I don't really understand electronics. All I know is if I swap out the 6v motors for 12v motors and add another 12v battery. The car could still be the same speed. It's all about the motors torque and rpm. Is that right?
 

Thread Starter

Marka1977

Joined Nov 24, 2018
19
What's the advantage of a 12v motor over a 6v motor? Will the 12v motor have more torque/power. But could still be the same speed if the rpm is the same as the 6v?
So if I want more pulling power then 12v motors would be better. And if I want more speed then I need to know the rpm of the current 6v motors and make sure I at least double it. Does that sound about right?
 
Last edited:

MisterBill2

Joined Jan 23, 2018
4,823
Many of the ride-on vehicles that use 2 motors do have a low speed/ High speed selector some place. And with the 2 relays it may be that your car has such a selection available. Have you located that switch? and which mode has been selected?
And how do you even know that they are 6 volt motors? In many applications a series connection is used for the low speed and then parallel for the high speed. Or it may just have a forward and reverse control.
In addition you need to consider the reality of the car moving at a faster speed, because twice the speed provides 4 times the force in any collision. In addition, there is probably no braking provision of any kind on the car, and that may be a problem at higher speeds.
So you do need to think also about the secondary results of making changes.
 

Tonyr1084

Joined Sep 24, 2015
4,020
Way way way back when my children were riding those electric cars, they had two 6V batteries. There was a dash board switch that could switch from low speed to high speed. I believe (going from distant memory) the batteries were connected in parallel for low speed but in series for high speed. In essence, I'm recalling those motors were 12 volt motors, just being driven at lower speeds by means of a lower power.

The company I was working for had a large field return from an oil rig. This was a HUGE UPS with dozens of large 12 volt SLA batteries - all used. I took a bunch home, they let me, and installed the best ones in their ride-on toys. You could charge the battery over night and the kids could ride those things every day for a week before you had to recharge them. The point is they were 12 volt batteries with a higher capacity than the two original 6 volt batteries. And 3 MPH was fine for the little kids.

If you want faster then go with a gasoline engine. Not practical in the plastic ride-on toys, so you'll have to either modify a steel ride-on toy or build one. My grandson just turned 7 a few days ago. He's wanting something to play with, both in terms of engineering and enjoying. Yes, like me, he's a tinkerer.

My plan is to get an old snowblower and use the auger and impeller as the gear reduction and use a small gas engine, maybe a Mantis tiller gas motor or a small Briggs & Scrapiron 2 HP and drive the auger. Speed would depend on tire size. Maybe a project for next spring / summer. Of course the smaller kids would want to ride it too, so I'll be keeping the speed down considerably. 3 MPH is a practical speed in my opinion. But with the older boy, changing tires to a larger diameter would give higher speeds, and must be done under the strictest adult supervision. I'll probably be exempt from that role. But hey! When I was a teen I built a supercharger for my mini-bike.
 

Thread Starter

Marka1977

Joined Nov 24, 2018
19
Many of the ride-on vehicles that use 2 motors do have a low speed/ High speed selector some place. And with the 2 relays it may be that your car has such a selection available. Have you located that switch? and which mode has been selected?
And how do you even know that they are 6 volt motors? In many applications a series connection is used for the low speed and then parallel for the high speed. Or it may just have a forward and reverse control.
In addition you need to consider the reality of the car moving at a faster speed, because twice the speed provides 4 times the force in any collision. In addition, there is probably no braking provision of any kind on the car, and that may be a problem at higher speeds.
So you do need to think also about the secondary results of making changes.
The attached picture shows the motors with 6v stamped on them. The battery for powering the car is 12v 7ah. I only know of a gear selector with forward and backwards. I believe 6v cars are for up to 3 years. 3 to 5 years recomend 12v and 24v above that age. My little lad Is coming up 6 soon so the current car is so slow for him.
 

Chris65536

Joined Nov 11, 2019
153
Wouldn't series starve a motor of some power. Or both. Is 1 not a slave to the other?
I works almost like a differential. If both wheels are on the ground, the motors' power will be close to equal. If one wheel is lifted, it will spin faster and the other motor will be starved of volts.
 

MisterBill2

Joined Jan 23, 2018
4,823
The attached picture shows the motors with 6v stamped on them. The battery for powering the car is 12v 7ah. I only know of a gear selector with forward and backwards. I believe 6v cars are for up to 3 years. 3 to 5 years recomend 12v and 24v above that age. My little lad Is coming up 6 soon so the current car is so slow for him.
A car that could fit a 3 year old will probably be a bit small for a six year old. Possibly a different car altogether will be a better choice. But quite likely nobody will sell the cars that go much faster.
A gas engine car is an entirely different beast with a whole lot of additional concerns that will need to be dealt with. Gas engines produce a lot more heat, and exhaust, and they use a fuel that can be dangerous under some conditions. Also, the drive chain needs to be a lot stronger, and you need a means to disconnect the constantly spinning engine from the wheels when you do not want it moving.
So my advice is to try different electric motors and more powerful batteries. There will be far fewer details to fight with.
 

Thread Starter

Marka1977

Joined Nov 24, 2018
19
A car that could fit a 3 year old will probably be a bit small for a six year old. Possibly a different car altogether will be a better choice. But quite likely nobody will sell the cars that go much faster.
A gas engine car is an entirely different beast with a whole lot of additional concerns that will need to be dealt with. Gas engines produce a lot more heat, and exhaust, and they use a fuel that can be dangerous under some conditions. Also, the drive chain needs to be a lot stronger, and you need a means to disconnect the constantly spinning engine from the wheels when you do not want it moving.
So my advice is to try different electric motors and more powerful batteries. There will be far fewer details to fight with.
That's what I am after. What 12v motors do I need. Obviously they need to be high speed ones, but which would be best. I can get another 12v battery to power them. (24v total)
 

MisterBill2

Joined Jan 23, 2018
4,823
To use the present gearing you will do better to get medium speed motors that are more powerful than the present ones. Or it may work out to get gear-motors and revise the drive system. Probably the present drive hardware is not able to handle much more power than the present motors can provide. If you have the room for them, adding another six volt battery in series with the present 12 volts will provide a fair increase in speed. That may be the simplest approach.
 
Top