Originally Posted by
Wildcat1971
I would not drill any holes if you racing on an outdoor track. my chassis is full of rocks and once i forgot to put my gear cover on and trashed the spur in 3 laps.
i drilled a hole, and countersunk it too, so i just run a standard 4-40 screw (any length, just as long as its under 3/8") and put a matching nut on the other end, since only change gear ratio once and awhile, when the time comes its alot easier/faster then taking the motor out if all you have is straight hex.
definitely easier with this car if you have a ball-end hex for the pinion tho.
http://www.amainhobbies.com/product_...iver-5-64-Blue
for example.