single-gear & other vehicle problems

Hi there!

I am trying to make a radio-controlled car with a single gear. (like in real rc-cars)
I set the max RPM to 35000, and reduced the gear-count to 1. But i don’t get it to work as it should. It turns only to about 1900rpm, and when i increase the Torque Curve it seems the wheels are spinning all the time.

Maybe someone did such a “one-gear-vehicle” already and wants to share his/her knowledge?!

  • Can someone explain me the graphs in the “vehicle debug overlay”?

  • Is the engine “good enough” to calculate such small values (i mean my car has about 1kg) maybe my problems result out of this:
    → lossing grip on certain rpm
    → get to much grip (after lossing it on high rpm, i spin, but keep pressing the throttle-btn, and when it gets the grip again, its on 40km/h in like 0,1 seconds…
    → when the vehicle stops, the rpm is still falling. (Shouldn’t it be 0 at 0 speed?)


For grip, playing with the wheel blueprint can help heaps with this. As for a single gear vehicle, you would want to look at the ratio of the single gear you are using, and adjust the value to make sure it’s not too low. Also you will probably need to play with the final ratio as well. The engine torque curve will probably need to be adjusted, so your power doesn’t come on too late in the rev range (wheels spinning at high speeds)

I’d try setting the max rpm to something like 8000, then adjusting the ratios and torque curve to get the desired speed. Keep in mind that the gear and engine setup in unreals vehicle physics can be a bit complicated to get a simple effect, so you might spend a fair bit of time playing with all these values.

Im not sure that the vehicle stuff within Unreal would actually be suited to an RC car. you would need to do a lot of playing around with the scale and weight and physical materials to see if you can get it right so possibly the default vehicle stuff is not really built to handle something like that.

Is there any tutorial or info about this? The six part Youtube tutorial on the UE channel isn’t very helpful. Vehicles in UE are quite difficult to tune up and I’m having a hard time to get an arcade feeling for the vehicles in my game.