LC Racing EMB1 - build question

[da999]

Just building this buggy - great quality, nice build.
Its the first time I have dipped my toe into a micro buggy.

Have got EZRUN brushless combo 25A ESC and 12T 7800kv motor (as in pic compared to my usual 540-size motor).

Cant believe how small the motor is! The spindle on motor is so small that the pinion wont fit centrally as when grub is tighted it is 'off-centre'. is it simply a matter of putting something around the spindle to make it thicker - if, so what do people use?

I'm wondering if I have got the correct sized motor?

Thanks