You got me looking up primary and secondary vibration with respect to engine balancing, thanks
A very brief statement of what I understand it to be so we aren't talking at cross purposes:
Secondary is weight / vibration / imbalance caused because of the piston's movement in the cylinder and that the piston will move faster during the rotation from 90 BTDC to 90 ATDC causing an imbalance or vibration at twice crank speed or frequency (hence secondary)...
The conrod seems to be considered part secondary (little end) and part primary (big end).
Is it that the secondary imbalance involves twice the frequency that means that it is of less importance or is it harder to make an improvement with?
I figure that the bigend is where most of the conrod weight is it would be similar to removing weight from the flywheel....
Then on the other hand...
The stroke of the CG13 is 80.5mm the average location of the bigend weight is therefore 40.25mm from the centre of the crank, I can't remember the diameter of the CG13 flywheel but the clutch is 180mm right? so a fair bit larger than that (lets say 220mm diameter).
So I guess long story short as frank said an imbalance or weight 40mm from the centre of the crank will have far less impact than one on the outside of the flywheel at something like 110mm (approx a third of the influence).
Is there a consequence of using the flywheel to balance the other rotating parts? ie the flywheel is stuck right down the back where something @ no 1 cylinder might be what it's trying balance....?
I was thinking along these lines because my time is free... but I'll put conrod lightening lower on my list, it could get real expensive if you took too much off I guess and probably not worth the risk.
Thanks for the reply frank, please point out errors in my musings.
