Why MaxSpeed could be faster on Clients than on Server at the same value?

[StarfireDev]

@gon

Im developing a grow up system where you start as baby, juvenile, subadult, adult, old.
Each stage have his own max values for walking and sprinting and added, for example, as baby a BaseWalkSpeed to 100 and BaseSprintSpeed to 250.
As Adult, 200 and 500. But what I can see when I play is that Client as Baby can walk and run faster than an Adult playing as Server.

I have to say that Client-Baby max FPS rate is 15-20 and Server-Adult is 70.
Can a difference of FPS make you faster against all logic?
How can I skip that problem and make Client run as its proper speed?

Thank you.

Did you check if the speed variables are updated in both Server and Client with the same value?