PDA

View Full Version : Ball diff changes...


HaCo
2007.07.15, 04:44 AM
Hi,

I couldn't really find a topic where this fits in, so I started a new one.

First of all, few weeks ago I started to get interested in F1. One at our club has an F1 with a ball diff which is sooo smooth and allmost doesn't slip at all. I started wondering, what the hell, why can't I get it like this on my MR02. I read here somewhere that the diameter of the gear is bigger, and that the balls are further away from the center and that helped to make it slip less, though keeping it smooth.

Now, also a few weeks ago I noticed that PN brought out just another delrin gear for a ball diff. There was nodthing special about that. Also ATM brought out a complete new ball diff for the MR02, I didn't really see any difference, except some small changes. Until today. :)

It's stupid, but suddenly I noticed that the 1) the PN gear had more holes then the previous ATM one. It went from 6 to 10. 2) If you look at the rebuild kit that goes with the new ATM ball diff, it has 10 balls too.

I don't know who was first, but it is clear they learn well from eachother. :)

The PN Diff Gear and Diff:
http://www.pnracing.us/new/product_image/328_1.jpg
http://www.pnracing.us/new/product_image/273_1.jpg

The ATM Diff and rebuild kit:
http://www.rcatomic.com/main/products/1/AR213_2s.jpg
http://www.rcatomic.com/main/products/1/AR214_m.jpg

Anyway, my question now is, has anyone tried one of these diffs with 10 ball? Is it smoother then the 6 ball versions? I can imagine that it will become heavier and that these ceramic balls are become more interesting too. Will it make my ball diff smoother to, with less slip?

Also, a very hard question, can someone tell me what grease is best choice to rebuild my ball diffs? I tried several here at home, even tried dry, but allways have different results. The best one now is no longer available anywhere (some grease that was laying around on my desk ;) ).

SaiTam
2007.07.15, 08:53 AM
Try Kyosho Ball diff grease, about $8 a bottle

The stock gear diff, however, is actually quite good believe it or not.

tribe
2007.07.15, 11:04 AM
I've had a PN titanium shaft diff (with 10 balls) for over a year now. Great diff, very smooth, no slip. I use the Kyosho ball diff grease as recommended by Kenon.

color01
2007.07.15, 01:13 PM
Then the question becomes, which is better: 1/16" or 3/32" balls? I think 3racing was the first to come out with a 10 ball diff, the KZ-07 has been on RC Mart since long before PN and Atomic released new diffs. I believe the 3racing one has 1/16" balls, it's very smooth but the grease creates more resistance overall than your typical Atomic or Kyosho diff. I should flush out the grease sometime and try it again.

And the GPM 12 ball diff is supposedly very good after extensive modification.

HaCo
2007.07.15, 03:26 PM
Thanks for the advice on the greace allready!

color01, that is some interesting info too.

This might be interesting too. A while ago, I think may, Kawada presented some tuning stuff for the Mini-Z. You might guess it, also a diff, with 12 balls.
https://sv18.wadax.ne.jp/~kawadamodel-co-jp//cargo/image/TZ01M/1.jpg
https://sv18.wadax.ne.jp/~kawadamodel-co-jp//cargo/goodsprev.cgi?gno=TZ01M

So, the extra balls, are they worth there money? :)