The stock ones are prone to failure because they are sintered which sounds cool but means they are made of powdered metal. They will break because of fatigue or simply from the simple impulse load an impact gun can put on them.
Oh And good work Marc! Can they be had in a wider belt vversion?
-Chris
'91 Audi 200 20v - Revver/BAT project '91 Audi 200 20v Avant '01 Anthracite M5 '90 M3 '85 Euro 635csi '12 X3 E34 530i (maybe rear-mount soon)
Are these "0 balanced" when bolted to stock crank pulley? I found out local machine shop can balance my single mass flywheel conversion, but not my crank pulley with my newly installed billet timing belt gear. I really want my damn S6 to be running again!
I have a VEMS just sitting there.... meth kit waiting....
I don't think that you need to worry about balancing the small cog gear. Since it's billet it should be very close out of the box, and it's so small that even if it was greatly out of balance you would never notice it.