[SV650rules]

To test if it will work with heavier weights get some plumbers solder (its about 5mm diameter, most hardware shops like B&Q sell it) and wrap it either round existing weights (if they have a protruding section ) or as near to end of bars as you can get, you can easily add and remove weight in this way. If the extra weight does not damp vibration you needn't waste money getting heavier weights - and need to look at something else as a cure for vibration.