Spinning gears, need object to spin about 3.5x faster Pretty new to Blender and have been struggling with even getting this to work, but now it does. A big gear is parent to a smaller gear and, via drivers, I have them both spinning the same direction and at same speed.  Thing is, I want the small one to spin about 3.5x faster than the big one.  Of course, this is just part of my project, but one step at a time.

I followed the YT below as to how I got to this point. Start @ 2:44. I had to slow it down big time and pause it, rewind, etc.  Days later, I'm to the point where I am trying to vary the smaller gear's rotation speed.

https://www.youtube.com/watch?v=M2P1JR2ko6I

My big gear is 50t and smaller one 14, and I have a chain to connect them. My objective is to have it all in sync. In case it matters, its supposed to be a motorcycle chain and sprockets.

Thanks.

Here is one of my feeble attempts at getting the big gear to drive the little one. Rotate the axis in center...they both turn.



Dang it!  I can't post a link with what I hoped the finished product would be like...but its like Paul's response..just my gears and a motorcycle chain.
Use a Generator Modifier for your driven smaller wheel.


Select the smaller wheel, go to the driver's properties shelf (N) and add the modifier. Increase the value pictured below. Now the wheels are spining with a different speed.