Con-rod balancing

"You balance rods by making sure they weigh the same (you also make sure the end to end weight distribution is the same for each rod). You balance pistons the same way. If your reciprocating masses are not balanced you will get some pretty bad vibration."

One way to do this if you don't have any scales is to use a piece of string or cord stretched between two points. Hang the rod off the string and see how far it dips - then compare this dip with the others. That was a Beavis tip for pistons, but it should be good for rods as well...

Con-rod clearances & long strokers

"If the longer stroke on the 1275 and 1098 engines causes problems with clearance on the non-synchro 1st gear trannies, then why is there no problem with the 997 Cooper engine, which has the same long stroke as the 1275?"

"997 might have same stroke/length as 1275, but the bigends are smaller. Hence the need for them when you restroke the crank for the 1380's and 1440's - They've shaved off a bit of the crank in the restroking process and hence your standard 1275 conrods no longer fit and you need the cooper jobs with the smaller big-ends."

Info from Ivor Kruger 29/12/02

07 June 2003