The old style pins on my 743 where 31.8mm in diameter , I was told they went to a bigger size on the 753 at some point. Does anyone know what size and can they retrofit a 743 ?
I know my 753 and 763 both run 1.5" pins, the 743 used smaller, i don't know for sure, but from memory they were 1 1/4"
I honestly don't know how much more of an advantage a larger diameter pin would give you. There is more to wear yes, but the smaller ones had more than enough strength as to not break.
As for larger diameter and your older machine, if the taper is the same, remember that your taper will bottom out in the arms and be left with maybe 1/2" of taper still sticking out of the arm before it goes into the boss of the bobtach. The "possible" problem you may have here is the bushing when it wears will wear on the inside where the pin is parallel. The taper part won't be touching and its possible it will deform the bushing and when you need to replace the pin/bushing you won't be able to remove the pin. Its possible it will reduce the sufrace area the pin has on the bushing too.
Just a few things to consider before you throw over sized pins at it. Not that you should need to replace then again with propper greasing.
Its only a thought though!
