ok, lets think about this.
1) take wheel off and feel for it
2) take hex off and feel for it
3) take the pin out and feel for it
4) take the bearing outs and feel them.

Start from the outside and work your way in.

Oke, I'll do that.

While I was spinning the wheel, I noticed this:
quality sucks, because youtube is still processing it..
http://www.youtube.com/watch?v=gS-KYbYxgII

It's like there is some kind of play on the axle and inner ring of bearing.

1) take wheel off and feel for it
I can feel it

2) take hex off and feel for it
Still there..

3) take the pin out and feel for it
Still there..

4) take the bearing outs and feel them.
Feel like brand new bearing, which they are.

replace hub??

car has done 5 races and some practice rounds..
Still pretty new. also, the bearings fit snug so I think thats not the problem.

What is a proper gearing for the buggy with a 7.5sensored motor?!

how much kv?

I only use 1 shim per axle instead of the 2.

So you can move the axle more towards the outside of the buggy?
And there will be a tad more clearance at the little notch,
I'll might try to do that.
Thanks

start around 78/22 then gear from there

Check how tight you have the hexes screwed down. They should be just snug enough to not come off the axle.

im running 78/20...

How about this keep it lubed..... Does the car do anything wierd when your driving it and you cant feel it when your driving right? If it still spins free just drive it. Sometimes it goes away when after some club racing but its not affecting your car... It does not seem like the axles are the problem. If its the bearing it will eventually get worse and come apart. I bet when you put the wheel on it spins free and comes to a slow stop. If its going clunk clunk as its spinning it cant be the axle. most likely the bearing

I didn't run my B4.2 since I got the problem.
I'm going to look further into it in the eve.

Do the yaiba hubs develope slop like the blue ae hubs?