Oh my. That's a can of worms I happen to be going through right now. 4-gears have all sorts of mechanical issues.I noticed that my new Auto World 4-gear cars have wobbly wheels and are gutless. So I'd like to fix them up.
I was just sitting here wondering about that very thing. When I lowered my MG+ it stuck to the track great, but we ran my wife's tonight and it wasn't even close. I could feel the difference when I lifted them off the track. I ended up putting stronger magnets in hers and it now has a little more downforce than mine with stock magnets, but not a lot. I'll measure and see if there's a difference. Thanks for the tip.We found that with Mega G+ cars with some chassis the traction magnets can be lower in the chassis. Even if the magnets were the same strength not every car would have the same amount of magnetic downforce. For that reason we have a spec for the distance between the bottom of the magnets and the bottom of the chassis.