@major
Thanks a lot... for now I don't want to mess too much with the mechanical part. Winter is coming here (up north) and I'm limited in garage space and tools. During the summer I can go to my dad's garage where we have a lot more space and tools.
So I will take your recommendations and try to setup that thing to run at a higher RPM and choose the appropriate gear for now.
I'm still waiting at Curtis Instruments for the motor learning procedure so I don't want to push that RPM too high.
And I also need to evaluate and choose what batteries I'm going to purchase.