First time posting, so apologies if this is in the wrong place....
My son and I built his new Plasma Edge II over Christmas, which was great fun. When he came to try it for the first time, it made a terrible clicking sound when it pulled away. Once it was moving it was fine and the noise went away, but it really was a horrible plastic grinding sound. I tried sticking my ear around the car and thought it was diffs or drive shaft, so I replaced the drive & prop shafts for Fastrax ones, and also bought a replacement standard diff set (Spare part G). I replaced all the parts (and was much more liberal with the anti-wear grease), but the noise is still there.
The interesting thing is after about 5 mins of run time, the car stopped moving. When you press the remote control to go forward, you can hear the motor turning and whirring, but it isn't driving the spur to the diff at the back. I've taken it apart again, and it looks like the pinion on the motor is not biting enough - if I hold the wheels and press the accelerator, the pinion slips on the spur and makes the same noise, so I'm sure this is the problem. I've gone back through the instructions several times (there's a kind of housing on the motor and you line up the screws to where it says "17" and this all looks OK), and I'm stuck now on what to do next. When I was young and had my Tamiya Falcon, I would have gone to my local model shop, but there aren't really any in my area now, and I can sense my son is losing some interest in it.
As the motor is screwed into position to the chassis from the underneath and it slides onto the housing on top, there isn't a lot of play on it where I could try to move it. I was thinking of looking at an 18T pinion, but wasn't sure if that meant I would need to upgrade the spur. Am I missing something obvious here, or has anyone else come across this before. I can't believe its a problem with just my individual car, given the amount that Tamiya produce, so I assume its something I'm doing (or not doing).
