I don't know if I'd bother with weights. Commute a few times on a big knobbie full suspension bike. then your hybrid will be like a feather. You'll destroy those kids off the line! That's more or less what I did.... commuted last summer and this spring on my heavy @ss mtb. Switched to a road bike and even loaded, I'm 200% quicker off the get go and can finally drop peeps here and there. Still can't hang with some of those damn fixies, though.