Gear up kits

What is the difference between primary and secondary gear kits, and what difference does each make?

What kind of scooter do you have?
A Suzuki Zillion?

And what is your setup/why do you want to know about the gears?

Yes, I have suzuki zillion. At the moment I just have a shity giannelli exhaust which I plan on replacing. At the moment i'm just checking prices of parts and was wondering if I would need both kits or just one. My main plan is to go as fast as possible, any advice on the best parts to go for would be helpful.

You will only need a gear up kit if you're running out of your variators range too soon and you have enough torque to be able to use the new gears (ie when you have a 70cc cilinder).

With an all stock engine with just another exhaust you won't have much use for a gear up kit.
If you really insist on it you could try a set of LC gears if you have an AC engine (though I can't remeber if they are different for Suzuki engines).

i had a gear up kit on my old speedfight and i hated it and tuck it off , but to be fare i only had 9bhp out of my 70cc "speedshite"