What motor frive gear should I choose ?

[Laurent JOËTS]

Hello,

I found a basic brushless combo "Hobbytech Xtronics".
I bought it without drive gear.
Could you help me to choose one here : https://www.conrad.fr/ce/fr/Search.html?search=pignon+moteur ?

Thanks ;-)

[Laurent JOËTS]

I calculate the module of the central wheel, and I found 36dp. Is it ok ?
How many teeth should I choose for my pinion ?
I think the smaller will be slower...

Thanks...