That doesn't really help. Why would I do that? What does that tell me about FDRs/rollouts? As a random example, a 72T spur and 47T pinion gives me the same ratio as an 84T spur and a 55T pinion. So why would I buy a larger spur when the same FDR/rollout can be achieved with the spur I have?

I'm not being a smartass but if you advise something like that, which isn't really an answer to my question then please explain why.

What is the reason for running larger pinions/spurs? I see a lot of people do it now so there must be an advantage but I can't get an answer as to what it is.