Pistons and conrods weights

[JEAN-NOEL]

Hi,
crank balance factor is of paramount importance, mainly on 650. I think it is necessary to know, for instance :
For pistons complete with rings and clips the exact weight for :
- GPM - GANDINI Std - +20 +40 +60
- JP - std +20 +40 +60
- other brands...(I don't hope to find Hepolite, AE, ALCAN, but...)
For conrods : total - big end - small end weights for :
- AMC
- Ridgecrest
My G12CSR with JP Pistons +40 is very unpleasant. I am afraid to leave it idle on the centre stand so the vibrations are unpleasant: the bike goes back !

[cf160]

Someone mentioned on another section of this forum that JP pistons were VERY heavy and could cause the misbalance and vibration. There are Heppolites around although more scarce by the minute. You might consider some used heppolites . I assume you are dealing with post 1959 650's? Those pistons are more difficult to find .