i keep all my rc's plastic, aluminum is expensive and can bend and if it doesnt bend or break will break the plastic that its attached to. just my opinion. i do have a tsunami ultrawide coming on wednesday [sm=thumbup.gif] and it comes with extended aluminum arms. The spur gears are the gears that the clutch bell on the engine mesh with(transmission gears), they are plastic and are known to strip. on rc's.

http://www.clermontmotorsports.com/s...le-gear/Detail
http://www.clermontmotorsports.com/s...le-gear/Detail