[quote="jbcollier"]Still on my first driveshaft but I did shear a rear axle.
Looks like you've already found the next weak link.....
Apart from transferring the drive to the rear wheel, the torsion driveshaft is designed to twist slightly to absorb shock loadings, as might be caused by bad gearchanges for example. Fitting a thicker/stronger driveshaft reduces the chances of fracture due to shock loads, but allows more of the shock load to be applied to other components in the drive train due to absorbing less of the shock load itself. The rear axle is relatively thin, and the splined section holding the crown wheel is the vulnerable part - I've stripped down rear axles from standard machines, and seen a fair amount of twisting of the axle between crown wheel and bearing mounting section.
My brother ran a modified LD for a while, and got tired with snapping standard 150 driveshafts, so he fitted a thicker version from a 125 LD. No more snapped driveshafts, but one day he attempted to pull away from traffic lights, let the clutch out and nothing happened - the axle had completely sheared between crownwheel and hub.
I'm not aware of any LD rear axles other than the original type, but an uprated version made from higher quality material would seem like a sensible idea.....