Originally Posted by Chickentrader
The CO1 magnesium bulkheads use 10 x 6 x 3 bearings for the layshaft; but the red CO2 bulkheads use 12 x 6 x 4 bearings, and no plastic inserts. It is possible that the plastic inserts will fit the red bulkheads however, and maybe the 12 x 6 x 4 bearings will fit the magnesium bulkheads if you don't use the inserts. Perhaps Patrizio will offer magnesium bulkheads for the CO2 with the plastic inserts sometimes in the future; we used the magnesium bulkheads in our CO1, and we never experienced any cracks in them.
The CO2 use plastic eccentrics for the rear diff though, and they are meant to dampen vibrations.
The magnesium bulkheads fit the C02, this part hasn't changed.
With the Magnesium bulkheads I would advice to check the bearings very regularly since they are very small for the amount of loads they have to take.
The standard bearings also fit the magnesium bulkheads but this is not advisable as the bearings will eat away the magnesium very quickly.
In generally I would advice to check the two speed axle bearings regularly, especially the one on the gearbox side, together with the clutch bearings these are the most stressed bearings on the car.
I actually prefer ceramic bearings for the two speed axle and clutch, these are a lot more durable.
Regarding the two speed screws coming loose, make sure you don't over tighten them. There is very little material left for holding down the screws so they strip quite easily. Once you have overtightened them your spur will wobble or the screws come undone. To be sure you can also add a drop of ca glue in the spur gear before tightening the screws.