Help with skipping motor

[GreenSalami]

Hoping for some advice.
I converted an old pedal kart to add a motor from a cordless drill (Ryobi 18V). I know there are better motor option but this is the set-up I'm trying to make work.
Anyhow, I've got a 10T motor sprocket going onto a 40T axle sprocket with #25 chain. Got 10" wheels and the whole thing isn't too heavy, maybe 20-30lbs? Drill is set to #1 setting with max torque, low speed.

When I run the motor with no one sitting on it, it works fine. If anyone sits on it to ride, my 35lb kid or me (definitely more than 35lbs) - it sounds like the motor skips. All the gears/sprockets are secure in place, nothing is slipping. My gear ratio doesn't seem too high? Is it just that the drill is not powerful enough? I've seen some run on harder gear ratios than mine. At this point I just want the thing to work, willing to sacrifice speed, etc.

 

[Functional Artist]

Howdy &

A 10T drive sprocket & a 40T driven sprocket only gives you a 4:1 GR (gear ratio)
...& IMO yes, that GR is way too high to move a loaded go kart, that's only being driven by a little dinky motor

That's why it "works" while unloaded
...but, doesn't (or can't) when "loaded"

Maybe try a 6:1 or maybe even 7:1 GR
...or a bigger motor
...& see how it does

 

[jrstlmo]

I believe your motor is too small. DC motors produce 100% torque at zero RPM. It works without a driver because the load is small compared to the motor. With the driver, the motor is too small compared to the load. The skipping may be the motor overloading and shutting itself off, and then attempting to rotate again.

 

[redflash]

jr's right.....experienced same issue.

 

[JessieJim1]

The issue you're facing might be due to the drill motor not being powerful enough for the load. Consider upgrading to a more powerful motor or adjusting the gear ratio to improve performance. Ensure weight distribution is optimal and prioritize safety.