Chris-PA
Where the Wild Things Are
Drive Links
Yes, and in order to get the chain to mesh, the circumference of the 0.325" must be 11% shorter than for the 3/8. Therefore by definition the drive sprocket diameter must be 3.5% less for the 0.325" chain.
So thinking about this fresh, it depends on what assumptions you start with.
Scenario 1: For a given engine rpm, there will be the same number of cutters passing any point per second, so the cutter load is the same (if the cutters were the same), and then the gear ratio gives you a 3.5 lower load on the engine.
Scenario 2: For a given chain speed in inches per second, the rpm will be higher and there are 11% more cutters passing any point per second. So the chain load is 11% higher, the gearing is 3.5% lower, and the engine sees a 3.14% higher load.
So which is it? Probably in between. The engine will rev higher than in Scenario 1, but not as high as in Scenario 2. The typically smaller cutters will add in there too. In terms of how fast it cuts, it will depend on the torque/HP vs. rpm characteristics of the engine, etc. That's probably why they use it on smaller saws as it allows them to rev higher.
