Originally Posted by
synap2012
Ball Diff All day, Everyday!
Smooth throttle in turns, and WAY more adjustble
*I wrote a long reply yesterday, accidentally clicked the wrong tab and closed the page, felt so sad I can only write it today.
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My problem with ball diff is that, it's working great most of the occations, but in this situation:
1. track is a bit loose (i.e. our medium grip indoor clay, but one day after rebuilt to new configuration, the track is very dusty somewhere).
AND
2. there's a jump soon after the corner, landing on a flat surface, and need to keep on accelerating hard for the next jump.
I'd like to accelerate a little before it lands onto the ground (17.5t need to get the power out).
once the two rear wheels doesn't touch the ground at the same time, it will quickly diff out, and the car will just spin out. Or just doesn't want to go straight.
That day I ended up tighten the diff a lot (yes ball diff is easy to adjust), it helps on that situation, but sacrifices the cornering agility. Slow but steady.
I used gear diff with 3K oil the next day, it's just working fine. May be the mass of the gears, or the diff oil functioning. The diff feels loose and smooth, but it doesn't diff out on landing & accelerating situation.
*most of other cars uses ball diff as well, and they shared the same problem when the track is low grip.
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and for 17.5t NR class, ball diff requires less maintenance.
I need to rebuild my gear diff every 1-2 months due to the spacer in the diff gets deformed, and then it will leak heavier and worse.
http://www.rctech.net/forum/11758337-post18805.html, and yes, I did listen to that guy and built the diff correctly without overfilling it, the spacer is still deforming, and I still can't find a way to buy just the spacers.
While since 17.5t doesn't have that power to damage the balls, it can last 3 months easily without even a rebuild (a friend told me his ball diff has been there for at least 3 months and still good).