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View Full Version : Ball diff - best practices for adjusting?


vertex
2002.03.22, 03:34 AM
Hi,

Is there anyone with experience in ball diffs that could give some generic guidelines on how to adjust it?

I'm looking for information like:
Slippery surface - set ball diff hard/loose
Make car understeer/oversteer - set ball diff hard/loose

/Henrik

funkydog
2002.03.22, 05:20 AM
well, this is how i think it works with real diffs, and it's somewhat the same for the mini-z

Normal cars have an open differential-no resistence-so the left and right wheels can move independantly of each other. This is good for cornering since the inside wheel doesn't move as fast as the outside wheel. THe problem is if one of the wheels loses traction and starts slipping the other wheel will lose most of it's power, and that's where you need the power. As an example, if you add resistance to one of the back wheels (put your finger on it), the power will transfer to the wheel with the least resistance.

The opposite of an open diff would be a locked diff, where both back wheels are locked together. Karts are like this. Problem with this is that when cornering, the inside wheel is forced to spin as fast as the outside wheel, so you'll get wheel spin-so this is bad for cornering.

Essentially, adjusting the diff, adds resistance to the wheels, somewhat like a limited slip diff that race cars have. THe more resistance, the more the car is like a locked diff. No resistance and the car is like an open diff.

So Basically:
Less Resistance = better cornering, more oversteer.
More Resistance = worse cornerng, more understeer, more torque (faster acceleration) and better for slippery surfaces.

Of course inbetween is always the best.

alduslai
2002.04.01, 02:33 PM
That's what i did to my ball diff.
1, Glue the plate together with the stand of the plate's, you only need one drop of aron alpha gel at both sides.
2, assemble the diff. remember to add enough grease to the balls.
3, fasten the ball diff a bit, just tight to make the plastic washer get's its preasure.
4, hold both sides of the wheel, try move the spur gear with your index finger tip. if your can turn it, fasten the diff, otherwise, try lose it a bit. The best condition is just fasten. So begin with a losen position, fasten it with half turn of the adjustment screw.
5, test your car. if you got usdersteer, fasten the diff by 1/4 turn, otherwise, losen it. Use 1/4 turn as your standard.