the stock driveshaft was crap, same on the tb02, it was too short and moved back and forth as mention in above post by jaun. the lighten drive shaft sold as a hop up was a little longer and could be used adding shims( I cant remember either to the front or rear, I'd have to get mine out to see) to minimise the forward and back movement and it worked quite well. Ive heard that the Tamiya Blue Conversion hop up(swapped out all the red bits for blue bits) had the correct length drive shaft included. You can get them somewhere on ebay but I never did. I think the cost is around $125 USD.

Oneway bevel spur strips teeth when you hit anything whilst on power. Usually you'd lose 2-3 teeth per incident.

Stripping can be reduced by better support of the gear on the oneway body. T made a CF ring that sandwiched behind the gear; Square made same in alu. Do not overtighten the 4 little screws, you'll warp the plastic gear... only snug tight & use loctite.

Original green shaft & early TB02 silver shaft were a bit short; later shafts were made 2mm longer & supported the bevel pinion better... surefire way to get longer shaft is the gunmetal lightweight hopup shaft or have found some "late" TB02s to have a longer silver shaft. Surikarn red shaft or the blue Conversion Kit shaft could be longer too but they aren't sold separately. Square also made a 3pc centre shaft which worked best of all.

I also put an extra bearing in the plastic support between the steering posts.

Gears are a consumable and if you ran out, you could ream out a balldiff gear to fit onto the oneway too. Later stocks of T SP bevel spur gears feel a bit beefier with more meat.

Either way... diehard evoIII wrenchers would keep a bagful of oneway assemblies on hand, once experienced one could swap one out/in in less than 60s ;) heck its only a 5 screws' job. Racers BiTD would lose 1-2 gears in a race weekend.

Then again even if your gear lost 6-10 teeth TBH haven't heard of anybody DNF a race just because of that gear failure. We'd mainly check & change it out only overnight or before finals.

Diff outdrives otoh... those were pretty brittle if you hit too many things hard. Lucky T gave us choice of both softer black & surikarn white plastics. (the TB02 diff sprue is just evil though)

EVO III Surikarn
 

My attempt at resolving known drive train issues.
Disclaimer: No original EVO II Surikarn parts were harmed during conversion :)

I see what you did there! Did you use EVO IV parts?

Does anyone still use their TB Evo 3?

Here's mine

https://scontent-sea1-1.xx.fbcdn.net...53428084_o.jpg


https://scontent-sea1-1.xx.fbcdn.net...90&oe=58C69263

it that the lightweight drive shaft in there?

I can't remember, it's the blue one, not stock. I have the tag somewhere.

No. I used a grey TB02 drive shaft, cut into three pieces to fit with Mugen Prime 12 drive cups and a couple of axle pins. An extra bearing was used in the front plastic support which was spun 180 degrees to used the lip differently.

Standard crown and pinion gears in the diffs but the shaft is no longer floating so all gears stay in place. Two pieces of the shaft were used as diff inputs with Mugen drive outputs. The third piece was used for the floating centre drive shaft.