Last time I was out with this buggy a gear stripped and I later found out the gears were not meshing properly. When my ball-race bearings arrived I took the car apart upgraded it and re-meshed the gears. Its now running at a decent pace and it great fun to drive!
I was filming in one hand and steering with the other which is way the steering’s a little crazy.
Shane's Shed 
Bit of a long shot but we’re the bearings metric or imperial?
Thanks.
Definitely metric but can’t remember the sizes but I am pretty sure most of them would be the standard size that’s usually on the wheel hubs of models.