Model: (Click to see more) 99993: Parts
Status: How To Guide
Date: 19-Feb-2009
Comments: 11
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After my first few drives of my 'new to me' Super Champ I was disgusted at how badly it handled. The main issue I could see was the lack of a diff and the solid drive rear end.

Solution: Fit a differential!

I almost fell off my chair when I seen the price of a secondhand well used Thorp Ball Diff and the wife seen too and said 'No Way!'. Only option left is to make one.

As promised, here is a guide to making your own Bevel Gear Diff centre for a SRB from readily available parts and at the fraction of the cost of an expensive Thorp Ball Diff.

The Instruction pages are pretty straight forward.

Suggested tools for this are a small lathe (electric drill mounted in a vice with a tooling mount to hold your bit works), a dremel, small fine files (thread files are good) and LOTS of patience!

What you need:

What to do with them:

After reassembling my Super Champ today and driving it for the first time with a diff I can honestly say it transformed the buggy. It now steers and doesn't spinout.

So far so good and it has not broken after many battery runs with the 4600Kv CM36s.

I'm surprised that no one else had thought of this combination of parts before with it being so simple.


A few have mentioned strength issues with the diff setup. The spline IS long enough and it's bonded with loctite (more spline than a Manta-Ray ball diff). The other issue was keeping the Final gear from becoming buckled or eccentric. To address the later issue I have modded my diff to add an alloy plate either side of Final gear that clamps the Star shaft centre.

If you liked those pictures, you should see these...
SRB Slipper Clutch


flux density


Wow. I like this mod. You are a genius , thanks for sharing



Yes you are a GENIUS, so much for thorp



this is simply awesome Mark!

Blacque Jacque


Hey, nice to see you brought this back Mark



Wow! Excellent. I have often thought if a mod like this could be done. Thanks for sharing and for the very detailed explanation. Now, where's that drill.



Did I understand that right Mark? A slipper clutch and a brushless system on an SRB!? You are crazy! Anyway, nice mod, I believe I have a spare gear to try this out with



I'm well impressed ! Whether I could do it is another thing entirely !! Brilliant work and a brilliant explanation, thanks for sharing with us



I forgot to mention the 7.4v 2s Li-Po that's in it too. I'm not crazy SRB is a perfect gearbox for it, primitive suspension just makes it intersting to drive. Fastest SRB this side of the black stump



i dont have an SRB but i think thats really creative, nice work!

Bin ^jammin^


Funny, i thought had already commented on this how to? Well this is a fantastic way to make a diff for the SRB, thanks very much for sharing the info here. I no doubt will be trying this out sooner or later, cheers



do you have a part number for the cross pins and the high-lift steering shaft? I will try to make a handful of these and if I am successful I will sell what I have minus one I will use.

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