Update on Fairmont saw specs.
I was looking at my excel calc sheet for this and see I had worked out the specs.
This saw uses .375 .050 chain and has an 8 tooth driver.
Without going thru the formula, the answers are as follows:
Chain speed @ 6 GPM is 2641 FPM and motor RPM would be ~5300
Chain speed @ 8 GPM is 3527 FPM and motor RPM would be ~7050
As an example, if using .404 chain, FPM for 6 GPM on this saw motor would increase to 2855 FPM and @ 8 GPM it becomes 3798 FPM with an 8 tooth drive sprocket.
It is how many inches of chain moved per revolution determined by RPM, pitch and tooth count.
Hope this helps in choosing a motor to make a saw?