833 Rake between gears.

For the A833, and the A230
I think there is exactly three reasons for grinding; 1) worn-out or broken brass, and 2) wrong oil, and 3) you physically overpowered the brass.
Well, technically,there is just one reason; there is a miss-match in speeds between the selected gear and the moving slider.
The floppy shifter or misaligned gate, just makes it a PITA to find gears.

I guess there could be a fourth reason; say you broke a fork-pin on the 1-2 shift but the tranny made it into second. If you then try to select third,Well, there is no way the brass can slow third gear down, cuz everything is still madly locked in second. I guess that could do some grinding all right.