Big end size

I cannot tell you the size of the con-rod eye itself but the big end size is 1.5 " and re - grind is in 0.010" steps, this should be stamped on the appropriate bob weight edge. (i.e. 10, 20 or 30). I cannot measure a con-rod eye at the moment, the garage is in turmoil as it's having a new roof on Thursday but will measure one as soon as possible if you can wait. 

Peter.

Attachment contains Technical Data

All good info Phil but does not contain what Barrie needs. My own experience of rod ovality came when I fitted new std shells to a well worn std 1.5" 99 crank. I was expecting that the  assembly would be a bit looser than ideal.But found that I rod would not fall under its own weight. I polished the crank journal with emery tape in a bandolier fashion and it then fitted fine. I was not really expecting it to last but it has. 25years on with regular classic use and plenty of 65mph cruising and short blasts up to 80 . Norton bottom ends are strong and tollerant of wear,especially strong on the lightweight. If you can get the rod re-sized ,good but as long as it all turns freely  without any play and you have a good pump I would not stress over it.

If checking for ovality then without a size just go on the difference between 2 measurements at 90 degrees apart, if it shows as oval does it matter what the size is as you need a new rod as you are going racing. 

Its the same size big end on Lightweights as for Domi 88/99 - if that is of any help