View Full Version : Sorry Ball Diffs again

2011.08.29, 04:02 AM
Sorry this is about ball diffs again, I tried searching but all I get is a bunch of unrelated search result. The question is simple though:

I just got my MR03 in the post so I tried to transfer the hop ups on my previous MR02 on to the new car, no issue with ball bearings but the TOPCAD ball diff I used to have doesnt seem to be a perfect fit, used 3 shims on the spur end but the spur still sometimes gets a bit too close to the stock motor mount "extra screwed on piece"

1. Am I supposed to omit that screwed on piece?
2. Is the ball diff from MR02 compatible with the MR03?
3. Say if I go with a new ball diff (current one weighs about 10.4g, feels heavy), lhs only has atomic and 3racing stuff, which one is better or should I built one up with the separate atomic titanium shaft, ceramic balls, etc?

Again I'm sorry to ask this kinda frequently asked questions

unearthed name
2011.08.29, 04:26 AM
Can you give us a picture? Do your mr-02 use the extra screw on piece? Because mr-02 and 03 back end is interchangeable.

2011.08.29, 05:12 AM
I don't have the original MR02 mount with me but I use the Topcad (I think its been too long) aluminium mount which doesn't have the screw on piece at all. Since you mentioned the backend is interchangeable, I'm gonna try and mount it on and see how it goes. Maybe the shaft for the ball diff isn't straight that causes the spur on the ball diff to touch on the edge of the screw on piece. I think I'm gonna go look for some lightweight ball diff, the Topcad one weighs twice the stock gear diff. Thanks for your help

2011.08.29, 05:16 AM
If you don't race outdoors, go ahead and omit the gear cover. It's mainly for rock protection, which... shouldn't be necessary, mostly. ;)

MR02 and MR03 use the same rear ends, so you are fine in that regard. And finally, Atomic stuff is generally better than 3racing, especially in the drivetrain department and for oil shocks. If you get yourself an Atomic diff package from your LHS you should be set for a long, long time -- when the balls finally wear out, treat yourself to a set of ceramic balls and you'll be set for a long, LONG time lol. I've been using the same set of ceramic balls in my diff for years, everything else gets replaced -- spur gears wear out, bearings bind, plates may wear out or bend, new lighter diff shafts become available -- but ceramic balls are for life. :)