big end rod size 88/99 twins.

You can get big end eyes resized, they plane a bit off the ends of the rod and the mating rod bottom and then hone the resulting smaller big end eye back out to size and circular.

Robert - I just measured a spare rod.  I find 1.607" in both directions.  (That is not even a round value in metric, at 40.82mm).  The micrometer scales 1.000 and 2.000 on its gauge bars.  Seems to be a rather odd value.  The nuts are not tight but all surfaces have been wiped clean and it's a snug fit.

Ps...is this the older design or might it be satisfactory?

I have a proper bore gauge - it's a bit more complicated to use, but much better that the "T" type.  But the T type is I think more likely to under-read.  I'll try the other one later this evening.

I am sure that I will be telling my granny how to suck eggs, but big-end eyes should be checked with the bolts torqued up.

Good point...I suppose if I ever reuse these rods I'll have to replace the bolts so I have nothing to lose if I tighten them properly.

I would imagine that once you know the true size the bore should be inside the rods, the most accurate way to measure them would be with a purpose made go no go mandrel/gauge.  Wonder if the factory used them.

The torque is low for alloy cap rods and quite critical. I cocked up on a model 7 thinking it was the same for all domi motors but as it tightened up on the journal at 25 lb ft I went to confirm in manual only to discover it’s as little as 15lb ft.

10 lb ft, the difference between free running or seized!

Jon