http://teamnovak.com/tech_info/view_article/26
http://www.petitrc.com/setup/durango...210_GearChart/
Your in the ball park there maybe drop a tooth
What are your settings on the esc?
Ask in the tekin thread as well, or have a look on their site for setups.
http://www.petitrc.com/reglages/teki...tsTekinRS.html
Although there aren't many astro setups there
Holes for airflow?
Is it running smooth without the pinion on?
Check the gearbox so its running smooth. I can recommend shims by the motor plate and don't hulk it with the screws