What Difference Between 4 Shafts And 6 Shafts Of The Drum Assembly?

What Difference Between 4 Shafts And 6 Shafts Of The Drum Assembly?

Q: What difference between 4 shafts and 6 shafts of the drum assembly?

A: 6 shafts are more balanced than 4 shafts, so less damage to the engine. The room for 6 shafts is less than 4 shafts, so 6shafts groove surface less deep, but finer; 4 shafts groove surface more deep, but less fine.